i doubt you have the miles built up (because if you did you'd probably know more about how they work), but in case you do, there's no need to go through the expense of paying for the transfer to another person. just give a card with a note saying that you're giving the recipient use of xxx number of your miles. when s/he wants to use the miles, you just have to book the ticket (this may require you to be in person at the airport or airline ticket shop, or you may be able to do it over the phone - which also costs a fee these days).
it's really far simpler to give the cash, as someone else already said. then you're not limited by airline or blackout dates or anything else.
one other option if it still exists is skyauction.com. if it's still around, you can bid on things like a ticket within a certain zone of the US. that might work for you.