Sounds like a good start!
For basic there is nothing about straps, but for the Specialist level it doesn't mention elastic or canvas, but I'd say elastic would be the way to go. I just answered the red part on my paint thread that I'll have to test to see.
Bracket or snap is your choice, I know people who have done both with the magmas. I personally use Velcro because of my body type (skinny).