If you’re at all associated with the Internet, beyond referring to it as “a series of tubes,” you’re probably away of a little site called TV Tropes. Caveat Browser: This site will eat your free-time like a starving man at an all-you-can-eat buffet. Anyway, a lot of the things listed on the site also list examples of places where things go totally wrong or depict a work in a satirical or sarcastic manner. You might come to think that the things on the site are things to be avoided, for fear of derision, ridicule or the simple notion that your work might suffer because of their presence.
They have a whole page on this subject, under Tropes Are Tools: Tropes Are Not Bad.
First of all, you can’t avoid them. Even if you say to yourself as you write, “This is X or Y trope,” chances are you’ve already written at least two other tropes into your work. Something that you considered entirely original will probably be pointed out as a trope and listed as such on the aforementioned site. Even if it’s pointed out as a ‘bad’ thing or ‘overused’, at least somebody’s reading your work, right?
Moreover, it’s entirely possible to use tropes well, or turn them on their heads. Look at Watchmen or Kick-Ass. Something that has its cool factor emphasized or the humor level turned up to eleven isn’t necessarily a bad work. In fact, such things can be rather successful if done right.
Finally, the existence of this trope listing serves a repository for quite a few cautionary tales on how not to do it. Consciously or unconsciously, if you see something listed on a trope page that reminds you of your work, and not in a good way, on that same page you can find examples of how the trope is done well, so you can see how to change your work to make it go down a different path than where it goes currently. Specifically, the path that rocks.
Take a look at TV Tropes. Browse around. Look up stories you like and stories you hate. Just let someone know you’re going in. Use the buddy system. And for God’s sake, don’t forget to eat something.