> A lot of lottery players will say use a birthday or something.

Ironically, this makes the ticket less valuable.

You can't do anything to change the probability of winning, but you can change the probability of winning at the same time as other players (which affects the size of the winnings). By picking birthdays (i.e. forcing the numbers to be in the first 30 or so), your prize, if you do win, is likely to be smaller than a really random selection.