I. Overview
Add Product Form plugins allows vendor to add products easier. Vendor will need to select categories and product type before enter product information. Each category will be related to an attribute set. The attribute set from selected category will be used to prepare for the product.
II. Relate attribute set for categories
From admin cpanel go to menu Catalog -> Categories. Click to a category to edit. On General Information tab you will see new option called "Attribute Set". You need to set the attribute set to relate to the current category.
You need to set the attribute set for all of your categories.
III. Vendor Add Products
From vendor cpanel go to menu Catalog -> Manage Products then click to Add Product button.
Vendor will see the add product form to let you select categories and product type. Vendor need to select category and child category to continue adding product.
Vendor can also search for category which you want to put his product on.
After the categories and product type are selected click to continue button to add product information. The attribute set from last child of selected categories will be used to prepare for new product.