You can use Amazon Smile just as you would the regular Amazon or Amazon Prime site. All the items for sale and the search parameters are the same, it’s just like you entered Amazon through a different door. When you have completed your purchase you can choose which charity will receive a small percentage of your purchase price. There is no additional charge to you. Simple as that !!
To access the Amazon Smile site go to http://smile.amazon.com/ . Use your normal Amazon login and password (or create one if you do not have one).
For details on the Smile program go to http://smile.amazon.com/about