Go to Stepmania website.

Click on either Windows or Mac. (for catalina/big sur follow this link to download OUTFOX)

Install the software (run or save)

Click on the software Icon.

 

WINDOWS

If you get an error message - check it. If it mentions  DLL file. Then follow this youtube link.

https://www.youtube.com/watch?time_continue=1&v=c5fxzdD3tZA&feature=emb_logo

MAC NOTE SKINS ERROR

note skins follow this thread

https://github.com/stepmania/stepmania/issues/1299

BIG SUR and STEPMANIA not Opening (OUTFOX)

Text instructions

Open applications

open Stepmania folder

Right click on Stepmania Icon

Click Show Package Contents

Click Open Contents

Click Open MacOS

Right Click on Stepmania UNIX executable and click open

Then just click behind the terminal page (don't close this window) when Stepmania opens 

 

To make things easier

And load do the same process again 

Right click on STEPMANIA UNIX and go to make alias, and put the alias file down on the right hand side of your tool bar or on your desktop

Then you can just click on that in future.