Here are my two cents. Not sure how familiar you are with Ableton so if it comes off sounding simplistic and obvious, apologies in advance.
If any of the songs you are trying to remix have live drums, learn to use the warp markers throughout the song to make them consistent so that they line up and are synced to the BPM so for example, if you were to play a 4 to the floor house beat behind a Nirvana/Led Zeppelin song, they’d match up and wouldn’t drift. This would be a non-issue if all of the songs you’re remixed have electronic beats.
In arrangement view (hit Tab key on Apple to switch from Session to Arrangement view), you can drag your song file there. And what’s convenient about Ableton vs software such as Audacity is instead of slicing and dicing the part you want to repeat, here, you can just drag the file shorter to the exact part you want. So let’s say you wanted to extend the intro four times. Just shorten the track to that intro part, then duplicate (CMD D) four times. I’m sure there are other ways to do this but I’m used to using Ableton this way. Where instead of making permanent edits, I just drag the file to whatever edit size I want.
As I type this, I know there’s probably a way to set cue points on the waveform and maybe just trigger those cue points similar to how Serato Flip does it (sorry, I don’t have Serato but I’ve seen tutorials) so if you’re used to that workflow, maybe do a search on setting cue points in Ableton as that might be another option for you.
Hope this helps!
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