The easiest way to turn Entries into Products is to add the included Product Details field to whatever field layout you'd like. This comes with a few benefits:
- A reasonably compact field type for storing typical product information: SKU, price, inventory, taxable and shippable status, weight and dimensions.
- The ability to switch on a plugin setting to automatically decrease product inventory as orders come in.
- Convenient, flexible template method for outputting Buy Now buttons, which contain the critical details that define products for Snipcart.
But you don't have to use this field type at all.
You can write your own markup and use whatever Events you'd like to control exactly how your site interacts with Snipcart.