Which way should I create this program? Visual Basic 2010?

(Will give best answer) Alright, I need to create a program where the receptionist of a spa kind of a place can see the price of a service(s). There are 4 service each priced differently. There are also discount coupons that customers can bring in to get 10 or 20 percent back on the service. Two text boxes at the bottom need to show the price of the currently selected item and the total cost. I have all the features set up and check boxes for the services and radio buttons for the discount. But after reading the chapter, I'm still unsure about how to format the code and where to use If and then. Please, note that I'm not asking you to do the whole project, just give me an example or a clarification on how to do it. I can think of an extremely long way to do it, but I can only work on this today, thanks!