There are several ways. I like using the interpolate feature, but there is the Move To feature as well as accelerate. If you are new to development I would REALLY suggest getting the Gamesalad Textbook. Search for it on the forums, it saved me tons of hours of research!
place it wheere you want it to start on screen all the way to the left or wherever. Go into the actor and check its x position so you know it. Ill use 30 as a exampls since thats close to the edge
Have a rule when self position x is less than or equal to 3o interpolate self position x to 450(thats an example as well)
Then ahve another rule when self position x is greater then or equal to 450 interpolate self position x to 30.
You can use whatever number you want, just make sure there the same in both rules
Comments
http://gamesalad.com/wiki/how_tos:gsc_pacing
Have a rule when self position x is less than or equal to 3o interpolate self position x to 450(thats an example as well)
Then ahve another rule when self position x is greater then or equal to 450
interpolate self position x to 30.
You can use whatever number you want, just make sure there the same in both rules