What is the easiest way to add padding above a module?

I am wanting to add some amount of padding above and/or below some of the modules. Some examples of this are on the home page at https://dev2.carneycorner.com where I would like to add some padding above the Most Popular Content module.

Another example is in the right hand column. I am using position sidebar-2. I would like to add some padding above and below most of the modules there and wonder if that can be done using the Advanced tab and making entries into Module Class Suffix or Header Class? Do you have any predefined classes to go with this template?

Here is a page where you can see the right hand column: https://www.dev2.carneycorner.com/blog/

Or, is there an easier way?

Or do I need to put in a entry into the custom.css file for each of these modules. I hope that is not the solution as that might be a lot of entries.

Thanks, Sean