I'm trying to get into doing a Super Meat Boy Any% WW speedrun, but I'm unsure on how to do a replay glitch. I'm also unsure on how to preform a bandage duplication. If anyone could help explaining how to do these glitches, that would be great.

hi, nice to see you're interested.

bandage dupe is performed by playing a warp zone level repeatedly. if you press the space bar on your keyboard after you beat the level, you'll see the standard replay screen even though you're in a warp zone (but not for long, because it's still transitioning to the next level). from there you can press the replay level button to play the warp zone level twice in a row (or more). if you get bandages each times, congrats, you've duped. the timing is a bit tight, since you have to hit both buttons before the level transitions, but it's not terribly difficult.

it has to be the space bar specifically. even if you remap keyboard jump elsewhere, or are using a controller, you will still need to press the space bar. this is why the glitch doesn't work on consoles. it's fine if you use software (joy2key) to remap space to an unused button on a controller though.

you can check "A Wrong Warp to Chapter 6 - The End Guide" over in the guides section on SRC if you want a second explanation.

replay glitches are a class of glitch. there's several different things you can do with them, but none are thought to be useful in any% ww (unless you count bandage duping as one), so don't worry about it.