WooCommerce looks great with all WordPress themes as of version 3.3, even if they are not WooCommerce-specific themes and do not formally declare support. Templates render inside the content, and this keeps everything looking natural on your site.
Non-WooCommerce themes, by default, also include:
Zoom feature enabled – ability to zoom in/out on a product image
Lightbox feature enabled – product gallery images pop up to examine closer
Comments enabled, not Reviews – visitors/buyers can leave comments, same as a post, and not product ratings or reviews
If you want more control over the layout of WooCommerce elements or full reviews support your theme will need to integrate with WooCommerce. There are a few different ways you can do this, and they are outlined below.
Note: Note that this is a Developer level doc. Select a WooExpert or Developer for help if you’re unfamiliar with code/templates and resolving potential conflicts, or use a WooCommerce theme. We’re unable to assist with customization under our Support Policy, as the issue is with your theme and not WooCommerce.
Theme Integration
There are three possible ways to integrate WooCommerce with a theme. If you are using WooCommerce 3.2 or below you will need to use one of these methods to ensure WooCommerce shop and product pages are rendered correctly in your theme. If you are using a version of WooCommerce 3.3 or above you only need to do a theme integration if the automatic one doesn’t meet your needs.
Using woocommerce_content()
This solution allows you to create a new template page within your theme that is used for all WooCommerce taxonomy and post type displays. While an easy catch-all solution, it does have a drawback in that this template is used for all WC taxonomies (product categories, etc.) and post types (product archives, single product pages). Developers are encouraged to use the hooks instead.
To set up this template page:
1. Duplicate page.php
Duplicate your theme’s page.php file, and name it woocommerce.php. This file should be found like this: wp-content/themes/YOURTHEME/woocommerce.php.
2. Edit your page (woocommerce.php)
Open up your newly created woocommerce.php in a text editor, or the editor of your choice.
3. Replace the loop
Next you need to find the loop (see The_Loop). The loop usually starts with a:

This varies between themes. Once you have found it, delete it. In its place, put:

This will make it use WooCommerce’s loop instead. Save the file. You’re done.
Note: When creating woocommerce.php in your theme’s folder, you will not be able to override the woocommerce/archive-product.php custom template as woocommerce.php has priority over archive-product.php. This is intended to prevent display issues.
Using hooks
The hook method is more involved, but it is also more flexible. This is similar to the method we use when creating themes. It’s also the method we use to integrate nicely with Twenty Ten to Twenty Sixteen themes.
Insert a few lines in your theme’s functions.php file.
First unhook the WooCommerce wrappers:
remove_action( 'woocommerce_before_main_content', 'woocommerce_output_content_wrapper', 10);
remove_action( 'woocommerce_after_main_content', 'woocommerce_output_content_wrapper_end', 10);

Then hook in your own functions to display the wrappers your theme requires:
add_action('woocommerce_before_main_content', 'my_theme_wrapper_start', 10);
add_action('woocommerce_after_main_content', 'my_theme_wrapper_end', 10);

function my_theme_wrapper_start() {
echo '

function my_theme_wrapper_end() {
echo '

Make sure that the markup matches that of your theme. If you’re unsure of which classes or IDs to use, take a look at your theme’s page.php for guidance.
Whenever possible use the hooks to add or remove content. This method is more robust than overriding the templates. If you have overridden a template, you have to update the template any time the file changes. If you are using the hooks, you will only have to update if the hooks change, which happens much less frequently.
Using template overrides
For information about overriding the WooCommerce templates with your own custom templates read the Template Structure section below. This method requires more maintenance than the hook-based method, as templates will need to be kept up-to-date with the WooCommerce core templates.
Declaring WooCommerce Support
If you are using custom WooCommerce template overrides in your theme you need to declare WooCommerce support using the add_theme_support function. WooCommerce template overrides are only enabled on themes that declare WooCommerce support. If you do not declare WooCommerce support in your theme, WooCommerce will assume the theme is not designed for WooCommerce compatibility and will use shortcode-based unsupported theme rendering to display the shop.
Declaring WooCommerce support is straightforward and involves adding one function in your theme’s functions.php file.
Basic Usage
function mytheme_add_woocommerce_support() {
add_theme_support( 'woocommerce' );
}

add_action( 'after_setup_theme', 'mytheme_add_woocommerce_support' );

Make sure you are using the after_setup_theme hook and not the init hook. Read more about this at the documentation for add_theme_support.
Usage with Settings
function mytheme_add_woocommerce_support() {
add_theme_support( 'woocommerce', array(
'thumbnail_image_width' => 150,
'single_image_width' => 300,

'product_grid' => array(
'default_rows' => 3,
'min_rows' => 2,
'max_rows' => 8,
'default_columns' => 4,
'min_columns' => 2,
'max_columns' => 5,
),
) );
}

add_action( 'after_setup_theme', 'mytheme_add_woocommerce_support' );

These are optional theme settings that you can set when declaring WooCommerce support.
thumbnail_image_width and single_image_width will set the image sizes for the shop. If these are not declared when adding theme support, the user can set image sizes in the Customizer under the WooCommerce > Product Images section.
The product_grid settings let theme developers set default, minimum, and maximum column and row settings for the Shop. Users can set the rows and columns in the Customizer under the WooCommerce > Product Catalog section.
Product gallery features (zoom, swipe, lightbox)
The product gallery introduced in 3.0.0 (read here for more information) uses Flexslider, Photoswipe, and the jQuery Zoom plugin to offer swiping, lightboxes and other neat features.
In versions 3.0, 3.1, and 3.2, the new gallery is off by default and needs to be enabled using a snippet (below) or by using a compatible theme. This is because it’s common for themes to disable the WooCommerce gallery and replace it with their own scripts.
In versions 3.3+, the gallery is off by default for WooCommerce compatible themes unless they declare support for it (below). 3rd party themes with no WooCommerce support will have the gallery enabled by default.
To enable the gallery in your theme, you can declare support like this:
add_theme_support( 'wc-product-gallery-zoom' );
add_theme_support( 'wc-product-gallery-lightbox' );
add_theme_support( 'wc-product-gallery-slider' );

You do not have to support all 3 parts of the gallery; you can pick and choose features. If a feature is not enabled, the scripts will not be loaded and the gallery code will not execute on product pages.
If gallery features are enabled (e.g. you have a theme which enabled them, or you are running a non-WC compatible theme), you can disable them with remove_theme_support:
remove_theme_support( 'wc-product-gallery-zoom' );
remove_theme_support( 'wc-product-gallery-lightbox' );
remove_theme_support( 'wc-product-gallery-slider' );

You can disable any parts; you do not need to disable all features.
Template Structure
WooCommerce template files contain the markup and template structure for frontend and HTML emails of your store. If some structural change in HTML is necessary, you should override a template.
When you open these files, you will notice they all contain hooks that allow you to add/move content without needing to edit template files themselves. This method protects against upgrade issues, as the template files can be left completely untouched.
Template files can be found within the **/woocommerce/templates/** directory.
How to Edit Files
Edit files in an upgrade-safe way using overrides. Copy it into a directory within your theme named /woocommerce keeping the same file structure but removing the /templates/subdirectory.
Example: To override the admin order notification, copy: wp-content/plugins/woocommerce/templates/emails/admin-new-order.php to wp-content/themes/yourtheme/woocommerce/emails/admin-new-order.php
The copied file will now override the WooCommerce default template file.
Warning: Do not delete any of WooCommerce hooks when overriding a template. This would prevent plugins hooking in to add content.
Warning: Do not edit these files within the core plugin itself as they are overwritten during the upgrade process and any customizations will be lost.
CSS Structure
Inside the assets/css/ directory, you will find the stylesheets responsible for the default WooCommerce layout styles.
Files to look for are woocommerce.scss and woocommerce.css.
woocommerce.css is the minified stylesheet – it’s the CSS without any of the spaces, indents, etc. This makes the file very fast to load. This file is referenced by the plugin and declares all WooCommerce styles.
woocommerce.scss is not directly used by the plugin, but by the team developing WooCommerce. We use SASS in this file to script the CSS in the first file easier and faster.
The CSS is written to make the default layout compatible with as many themes as possible by using % widths for all layout styles. It is, however, likely that you’ll want to make your own adjustments.
Modifications
To avoid upgrade issues, we advise not editing these files but rather use them as a point of reference.
If you just want to make changes, we recommend adding some overriding styles to your theme stylesheet. For example, add the following to your theme stylesheet to make WooCommerce buttons black instead of the default color:
a.button,
button.button,
input.button,
#review_form #submit {
background:black;
}

WooCommerce also outputs the theme name (plus other useful information, such as which type of page is being viewed) as a class on the body tag, which can be useful for overriding styles.
Disabling WooCommerce styles
If you plan to make major changes or create a theme from scratch, then you may prefer your theme not to reference the WooCommerce stylesheet at all. You can tell WooCommerce to not use the default woocommerce.css.
Add the following code to your theme’s functions.php file:
add_filter( 'woocommerce_enqueue_styles', '__return_false' );
With this definition in place, your theme will no longer use the WooCommerce stylesheet and give you a blank canvas upon which you can build your own desired layout/style.
Styling a WooCommerce theme from scratch for the first time is no easy task. There are many different pages and elements that need to be styled, and if you’re new to WooCommerce, you are probably not familiar with many of them. A non-exhaustive list of WooCommerce elements to style can be found here.
Examples
Storefront is the official WooCommerce theme built to the same exact standards as WooCommerce itself. The code is available on GitHub.
If you would like to see examples of other themes that have added WooCommerce support and with their own styles, we suggest looking at the following themes, which can be downloaded from their showcase pages on WpSupport 360:
Woocommerce Support
Malware Remover
Speed Optimization
WordPress Migration
WordPress Maintainers
WordPress Hosting