• click on Tools->Settings as follows:

• Enter your user password if prompted.

The Settings page will appear.

• Click on "Pricing, Products and Services" to bring the screen below.
  
  

You can create categories first if you can't find the category you want in the category list.
To create a category:

• Click Add in the Category list
• Enter the category name
• Select the type (product or service)
• Click OK.

In the Products/Services list,

• Click Add.

The Add Product/Service page will appear.

• Enter the product/service's description.
• Select the category.
• Enter the unit price.
• Enter the initial stock quantity (for product only).
• Click OK.

Your new product or service has now been added to Products/Services list.