ohhh ok so u need tips cause u haven't started yet . . . ok.
So wat i think you should do, which i seem to have a very big problem with, is try and hook the reader onto ur story. You don't have to start with "My name is Leon Irad and . . ." because, personally, i think that's kind of boring. Take the first sentence of my story for example "The worst time to be awake is in the middle of the night." which doesn't tell you anything about the character/s yet but gets the reader interested and have them want to know what's going to happen. Later you should definitely describe the characters (wat they look like, wat their names are, etc.) Ppl here tend to like longer chapters so i reccommend doing that. Also, add twists that make ppl go "OMG wat's gonna happen?!?!?"
Be sure to re-read and edit ur story before posting. I have a hard time doing this because I'm a bad editor and i'm too lazy to re-read my stories but it comes back to haunt me when serious writers tell me that there were a lot of errors in my story.
But my biggest advice? JUST START WRITING. No matter if it's something about horses, a girl with cancer, vampires, zombies, gangs, mind readers, just go for it! Write about anything that interests u. And remember, stories on top of the "hot list" didn't happen overnight. I'm sure writers like Canse12, DSadie, and darkangel35 had many many stories that they wrote before their "hot list" ones. Like me, i have so many stories on my computer right now that didn't seem to work or didn't even make it past the first paragraph.
So just start writing. If it's something u love, then I say go for it and dont back down!!
Leon