What do I need to do in development stage if the website is going to use SSL ?

Hi, guys.   I started developing website using .net recently, and this website(most pages of the website) is going to SSL probably.
My first question is that, Are there anything special that I need to do in development stage if the website is going to use SSL?    
Until yesterday, I thought SSL is all about configuring IIS to use a SSL certificate from 3rd companies such as verisign etc, and thought there is nothing extra I need to do in development stage.
However, when I used the createUserWizard yesterday, I got a error as following
 
The application is configured to issue secure cookies. These cookies require the browser to issue the request over SSL (https protocol). However, the current request is not over SSL. Description: An unhandled exception ...