While creating products, you can select the "This is a customizable product".
What is it?
This option is reserved for certain visuals, those for which you will let your customers modify the product.
For example, you can propose a product with the visual "I'm in love with..." and then let your customers choose the first name.
You simply need to install on your store a simple customization module, the offer is vast both on the Shopify app store and in the list of WooCommerce plugins...
If the product has been created with this option activated, we will not process your order until we receive the new design: this way, you have the possibility to send the new design according to your customer's wish.
Explanations:
Selecting the option
You can see here that we have added a visual "I'm in love with".
What you will see in the product list
This is what a custom product order will look like
Click on "Order details"
To modify the product, click on the Edition link
The editor then opens
Upload your final design
Here we have edited the original visual using an image editing app (you can use Photoshop, Pixelmator, Gimp, Paint, whatever you want) to add "my cat" to the design.
All you have to do is validate: the order can then go into production and we will send the personalized visual to your customer.