Are you waffling between more than one possible answer, or maybe just taking a stab in the dark? There will always be times when you think you know what the answer is, but you can't be 100 percent sure. Do you take a chance and write in your guess, or not? If the answer in question intersects with yet another maybe-it-is-maybe-it-isn't clue, skip it for the time being. Writing in wrong answers can lead you astray, especially if you're one of the brave souls who prefer to do the puzzle in pen. Instead, rely on the answers you know are correct to lead you back into safe territory.