Advice needed on cleaning up some script

Hi, I’m a complete beginner who ventured into the world of Flash and programming only a couple of days ago and need some advice on how to clean up some as2 script I’ve put together because I haven’t been able to find tutorials on everything.

The script below does exactly what I need it to do at this stage for a one time project i.e.

  1. Start an object moving in a certain direction on loading
  2. Turn an object to face a certain direction and have the object move in that direction.
  3. Make the movement perpetual (i.e. not reliant on continuous keystrokes or holding down a key) at a constant speed.

Apologies in advance if the following is offensive to anyone.

onClipEvent (load) {
upmove = 0.5

}
onClipEvent (enterFrame) {

if (Key.isDown(Key.RIGHT)) {
this.gotoAndStop(2);
rightmove = 0.5
leftmove = 0
upmove = 0
downmove = 0

}
else if (Key.isDown(Key.LEFT)) {
this.gotoAndStop(4);
leftmove = 0.5
rightmove = 0
upmove = 0
downmove = 0

}
if (Key.isDown(Key.UP)) {
this.gotoAndStop(1);
upmove = 0.5
downmove = 0
leftmove = 0
rightmove = 0

}
if (Key.isDown(Key.DOWN)) {
this.gotoAndStop(3);
downmove = 0.5
upmove = 0
leftmove = 0
rightmove = 0

}
speed = 0.5
_x += rightmove
_x -= leftmove
_y += downmove
_y -= upmove
}

My concern is that I arrived at point 3 above by banging my head relentlessly on the keyboard and employing an army of monkeys to sit and type random monkey-babble all day long, and no doubt there is a much prettier and more efficient way of achieving the same thing. Any advice on how I might do that would be much appreciated.

Cheers.

http://www.ezy-english.com