For example, if a simfile has steps on Light difficulty on dance-singles but you want to create steps for Heavy on dance-singles, using this option will copy all the steps from Light on dance-singles and put them in your Heavy edit and you can step from there. "Create from Source by Copy" - It'll copy the steps from the Source Difficulty + Source Stepstype combination and place them in your edit.If there are pre-existing steps on a simfile on one of the difficulties but you want to create steps on a different difficulty or a different Stepstype altogether and there is no existing stepfile information for this difficulty + Stepstype combination, some more options are left for you.Highlight "Edit Existing" and press Enter.Since you have Stepmania downloaded and you're trying to either create your own stepfile or edit a pre-existing one, I'm sure you know the summaries and differences between each difficulty and shouldn't need an explanation of what each of them would normally contain.
You can choose Beginner, Easy (aka "Light" or "Basic"), Medium (aka "Standard" or "Trick"), Hard (aka "Heavy" or "Maniac"), Challenge (aka "Oni"), or Edit.
First, you have to select the folder or "pack" that the song you want to edit is in.At the main menu, select the option (according to the Stepmania 3.9 default theme) "Edit/Sync Songs.".
There is no rule or guide line on how to step a song (AKA make the steps of a song).