If the opponent is catching and throwing your continuously off the stage, wait until you are barely under the edge of the stage and UP-B
If the opponent is going to hit you mid-recovery activate Slip-Counter. This is very tricky because if you miss the counter all of your forward momentum will die and you will have a MUCH harder time recovering.
side Bs will kill you if you use it less than half-way from the ledge when going towards a ledge so if you ever use it (which you should not in most cases) make sure you are going toward the center of the stage.