My approach is to employ folks with enthusiasm. If they're teachable, they'll figure out whatever pile of tools they get thrown into on the first task. Then they'll have some skills and the next task will seem less daunting.

Of course some mentoring is useful. But just the stuff that's pertinent to the task at hand; concrete help that gets them moving forward. Because, somebody is paying for results. And because producing results has a very positive effect on confidence.

I just offered work yesterday to a young person helping me at a big box store. I mentioned I was buying a device to test an Android build, and they got excited and started making cogent comments about the tool chain and devices available. I game them my card, and when they graduate in 3 months (from a local community college) I'll find them work on a client's contract.

The first project will cost me more than I earn from subcontracting them (because it takes me away from my high-rate work I would otherwise be billing). Maybe break even by the 2nd. But it's a sort of enlightenened-self-interest thing. If young people get into the field, everybody benefits.

And of course as an old guy with resources, I can afford to take some risks. Because it's everybody's job to look out for the other guy.