How can I show the Profit Margin on a quote

How can I show the Profit Margin on a quote

I want to be able to see the profit margin on the quotes.  I created a field on the product so I can enter the cost of the item, but I'm stuck from here.  I want the quote to calculate the total quote amount - cost - discounts.  I would like the gross $ amount and % if possible.  How can I do this?