Best way to arrange your products properly is to create some categories and subcategories through which your clients can find the matching products. These categories will build up your menu in the end.
It is that easy:
Enter the name
To create subcategories click "plus" and proceed in the same way
Use the arrows to determine the order of your categories
Click on the matching category and subcategory when creating a new product
Don't forget to save the changes and you are finished :-)