1. Log in to the admin screen and select Products.
2. Press "Add" to add a new product.
3. Enter in the name, price and code.
4. Select the "Options" field enter in the types you wish to sell, for example Small, Medium and Large. Press "Add New Type" to add multiple items.
5. If you want the different options to add to the price fill in "Adds"
6. Enable "Can have multiple options" if you want to be able to select multiple options (otherwise just one can be chosen).
7. Enable "At least one must be chosen" if you want to force the selection of one option.