In order to edit a product you need to go to your Shopify backend and locate the product you would like to edit.
Select “Products” from the vertical left-hand menu of your Shopify dashboard. You will be redirected to a list of your created products. Select the product you want to change from the list. When the product detail page opens, click on the “More actions” dropdown menu at the top of the page and select “Edit on SPOD”. Doing so will open the design tool. Simply edit to your requirements and sync to shop.
Click here to learn how to delete products.