Skint
I belive the way to go about it, without any previous experience, is to start at the bottom loading aircraft. Then progress to loadcontrol (or whatever you choose to call it) and from there work your way up (or down, depending on perspective) to become a loadmaster. Make sure you're well connected to whomever does the hiring.
Muppet Leader
It's actually 4 guys on contract, and rumours has it they're looking for a 5th.