Draw Offers: Rules & Etiquette
As a TD and player, I've seen many "interpretations" of a correct draw offer and I'm amazed at how many players of all rating levels are unaware of the correct procedure. With your clock running, you are to make a move, offer the draw, and then press the clock. However, if you offer a draw at any time, even when you're not "supposed" to, it's still valid.
If your opponent offers a draw before moving you have the right to (and should!) ask him/her to "make your move first and I'll think about it." If he/she finds a winner, too late - you can take the 1/2 point. A draw offer is irrevocable and in effect until the person offered the draw denies it or makes a move, and that person can take as much time as is on his clock to decide.
I witnessed a nervous young player offer a draw to a much higher rated adult opponent before moving, only to realize that the move he played was decisive and he actually tried to take it back, which of course he couldn't.
Also - is it improper to offer a draw to a higher rated player? Mixed feelings in the chess world on this, but it's my firm contention that it's the position that matters and not rating. If it's an "even" or unclear late middlegame or endgame position, the lower rated player has every right to offer a draw. I think the only exception would be in certain open events when a class player is paired against a titled one. Repeated draw offers, or one where the person offering is clearly losing are unsportsmanlike.