Hi There! I am in the process of building my Scout Trooper as well, I found this video series by one guy that looks pretty good... He uses a couple different sized of elastic - nothing that appears outside the regs, but you can get away with 1/2 and 1/8 elastic for quite a bit... When you launch the video, look to the right and you can see the entire series.... There are 18 videos, but about 1/2 are how he casts the pieces - interesting, but can skip them to the build part.
This is a good one for a boot video too.... The links above from Chopper are the fist place to start though. these are nice for a video of someone walking through and talking about what to do