How do I make a new stepfile?

[Acidic Rage]

I need to know how to make a new stepfile. I was planning on making stepfiles that I and other people around the world would like. But the only problem is that I have no idea how to create the stepfiles.

Is there a certain software you have to use for it, or can I go somewhere on the FFR website and make one?

Please help and give any advice/information that may or may not be useful. Thanks.