How to write a cliche
(Without it looking like a cliche)
STRIP IT DOWN
Take a cliche story, Twilight for example, and strip it down to the basics, forgetting all the sparkly shit.
Girl moves to new town, falls for the school untouchable, untouchable drops hints(in Twilight's case the creeper watches Bella sleep) Other guy likes girl, girl leads other guy on. Girl inevitably marries untouchable.
This may seem like I'm putting Twilight down, simply for the sake of it, so I'll do another one, that has the same base, but you wouldn't expect it.
Avatar. The very same Avatar with the blue giants.
Main character sent to a new environment(in this case, a new planet) and falls for the untouchable(native already promised to another) and they start to get it on. See? It's still the same basic plot, but two, incredibly different films.
All you've got to do is change the actual aspect of it(Example, They're usually put in a new environment, new school, new planet, change the characters usual environment, this gives them the chance to meet new people, and the untouchable, it dosen't matter where the place is, as long as it's different from your chosen base) You don't want your story to end up like Twilight, spice it up.
If you're reading this you're probably pretty crappy with your imagination, so this won't be easy.
Make a mind map of things you associate with the genre you're writing in. Throw it away. You obviously need a cliche to write something, so don't trust your imagination. Get someone elses perspective, maybe someone older with more experience. And I don't just mean in romance.
If you're writing a supernatural story look up the subject you're writing about. Stephanie Meyer obviously didn't or Edward would have eaten Bella when she realized he was a vampire, and don't get me started on the glitter. Watch lots of films in the genre of your writing, take ideas, twist them to your story.
Weave in ideas that will make your story seem more original, paint over the obviously copied ideas with good writing skills
Though some people find imagining things easy, others are not so gifted in that department, so for those people, copy, paste and edit.