You just have to keep your eye on the ball, your nose to the grindstone, and your shoulder to the wheel. Never say die, don't give up the ship, stand for something or you'll fall for anything, keep the faith, baby, gimme five, knock 'em dead, if ya can't beat 'em, join 'em, remember the Alamo, and keep on the sunny side of life...
Joss Whedon had a great way to avoid cliches -- he made up all his own figures of speech. Biggest problem with cliches is they sometimes wear out, and then your story looks like a period piece. You can watch any episode of Buffy and never hear an expression that was popular at the time but sounds ancient now -- 'cause no one outside the cast of Buffy was saying it when it was filmed.
If it sounds familiar when you write/read it, think of a way to say that you haven't heard before.