If you wanted to do it in two steps, it will obviously just jump from one place to another. In my examples I've used 20 steps as it makes for a nice msoothe, yet relatively fast tween. Now we know where we're going to and comming from, how far that is, and how many 'steps' it's going to take. How far we should move per step. Againt his is just simple maths.
Same principle applies here.
I use a counter variable which counts how many steps we've taken. I think most of you could go off an make your own working example now, but the next problem people face is the syntax because it does get a bit ugly the way some people do it. I've kept it as cleen as possible. Now that we know the logic, let's go back to our example. Grab the source for the movie above.