A common mixing up of similar words is lose vs. loose. If you often mix these up, try these hints.
From the Copyediting newsletter’s Tip of the Week email (my additions in red):
As Joyce Cheney, professor of English at Santa Monica College, advises her students:
1. Loose with its two o's should remind you that there is too much space[,] so something is loose as in a pair of loose (or roomy) pants. Loose also can refer to a handful of coins [think of the o’s as coins] that are unrestrained[,] as in loose change. Similarly, a person may be described as loose if he or she functions with few rules or boundaries.
2. Lose with only one o should remind you that something is missing[,] as when one loses or becomes unable to find or keep something or fails to achieve, as in to lose a game.
Try to remember just the first part—that loose has room in it, so it requires two o's—and see if that helps. You can even [test yourself] with Cheney's Loose or Lose? quiz.