As long as he's in the United States, it's easy enough for him to first get his own United account, and then use one of the 600 mile intro links to build from there. I don't pay to fly United- bad routing to where I typically want to go- but had signed up for a MP account at some point for a few free promotional miles, got a link for the 300 mile bonus, and then figured I might as well give the surveys a try and see if I could at least hit 10K at which point I could swap the miles at points.com at a horrible rate into something I might actually use. Instead, I'm now targeting MP freebies where I can find them specifically for plane tickets.
And if he's then hooked on his first survey program, I'd also suggest he later move on to MyPoints and e-Rewards for more United Miles, and then Swagbucks, where it's pretty easy to pick up GCs for Marriott, Hyatt, and SWA.
Speaking of... now that this program's been around for a while, is it time to move it over to S.P.A.M. where such threads usually reside?