GeX: I'll start with the scout surf, which is by far the easier maneuver (unless you have a joystick). Walk over to a wall, preferably in a light hull. Duck down. Recall your scout (using the scout command key, I think it's "r" by default) and then stop it (scout control + look forward) just before it enters your hull. Back away and then jump forward onto the scout. Now, order the scout to move forward (scout control + move forward, up arrow by default). It will try to fly forward and up to get in front of you, but the wall will block it from going forward, so it will just go up. (Of course, the wall is really irrelevant here, it just makes the ballancing act simpler. You can do this in the open, sending the scout in any of the four directions once you're on top of it.)
Now, the superjump. I'm probably the wrong person to answer that, but here goes. Due to an unclassified feature (AKA bug), it is possible to jump when you're already in the air. To do this succesfully you'll need at least two jump keys, preferably more. Kneel in front of a wall, walking forward. Release one jump key and, at the same instant, press another. If you time it perfectly, you'll go twice as high as normal. Slightly easier and more common is to take about four jump keys and simply rotate your finger around them, pressing them in sequence - you can get maybe three times as high a jump if you're lucky. For some reason the superjump works better if you are standing with one foot on a ramp and the other foot not. If you have a joystick (I don't) you can probably program a button to fire the jump keys with the proper (short) time delay in between.
Icebox, heck, in an unlaiden light hull, you can jump out of the arena in REDBLADE. Of course, you can scout-surf infinitely high (well, until you hit the bubble), so it's still superior IMHO. By the way, it's a good idea not to have anybody coming up behind you when attempting either of these maneuvers. If you want to practice, I recommend first trying to jump to the missile towers in bwadi, then jumping out of the arena in icebox from the corner, then in icebox from a side, and then out of redblade from a side. If you can pull that off, you're officially a superjumper.