Does anyone know much information on this?

I know from talking to people on sets that getting paid to be a make-up artist is almost as hard as getting paid to act... they do a lot for free, too, or for the cost of materials they use. So it probably would not be the best choice for a survival job.

Do you mean on a film/TV set, or at a studio?

Either way, I'm pretty sure you have to go to school for this. An actor friend of mine cuts hair in a salon; she makes great money and is still able to make auditions. However, she had to complete a two-year program first.

I mean like making a living doing this if all fails in life, and I am old as well (I don't expect to do this in my 20's/30's but in my late 40's).

A final back up plan, or a survival career in a hair salon.

Mystique:
If you mean to be a hair stylist for a salon, different schools have different programs. For instance, I was looking into Aveda, Here in NYC, its a 7 month program for hair and cosmetology if you go during the day, 1 yr if you go at night. It costs around $15,000 though, so save your pennies! Other shcools may offer different prices and programs, too.