If you need to use the Custom product builder to track the inventory but you don't have all the SKUs as a separate product yet we suggest creating a Parent product in your inventory that will contain all SKU.
IMPORTANT: DO NOT add custom product options SKUs as variants in the cpb_product product in Shopify admin – It will lead to bugs and errors.
1. Create a new product that will contain all SKUs as variants. This has to be a different product from the customizable product you are making! To create it: Open your Shopify store -> Products -> Add product. The product must be Active for it to work correctly.
2. Scroll down to "Variants" and flag the checkbox "This product has multiple options, like different sizes or colours". You can choose any type of the variants (Size, colour, material etc.) it won't matter for the CPB App. You will be able to put all types of SKUs inside the Parent product variants meaning it could be both colours and sizes etc. So you won't have to flood your inventory with such Parent products.
3. Add variants one after another in the field – they will appear in the table below the list. Click on the variant to edit it. On this page, you will be able to add SKU related to this variant and the quantity of the variant in stock.
4. Once you saved all SKUs you require for the product you can enable inventory management in the settings. Open one of your products in the App and go to Settings -> SKU management -> turn on toggle "Enable inventory management" and wait until you can see the "Inventory Tracking enabled" message. You will have to repeat this procedure for each product.
5. Now you can connect SKUs to options. Go to the options page (Product -> edit category) and put the related SKU in the SKU field. This can be done straight on the Edit category page or the "edit option" page on the "Inventory" tab. Please relate to screenshots (the screenshots are topical for the new interface). Save option and category.