Every girl has her issues and little features she wants to cover up. If it's a high forehead and cowlick you've got going on, well, you've got double the dilemma. Hey, there's nothing wrong with it, but you want to create the nicest face proportion so it's all about slimming down the size of your forehead -- or "fivehead" as Tyra Banks jokingly calls her own larger-sized forehead -- and cowlicks are just plain annoying, so you want to deal with that too. That's OK, you can take care of both issues at the same time, with the right cut.
Bangs cut straight across take care of a high forehead problem and a cowlick, all at once. As long as your bangs are thick and not wispy, you'll dramatically cut down the size of your forehead, creating a nicer balance on your face. As for the cowlick, well, no one will be any the wiser that you have one at all, because the weight of your bangs keeps it down out of sight, and it makes for much easier styling now that you don't have to deal with that sucker.
Getting a side-swept fringe is one idea if you have a high forehead and a cowlick issue. If you're able, have your fringe swept in the same direction that your cowlick faces, to make for easy styling. Otherwise, keep your hair parted off to the side a bit and "train" your hair by styling it in the right direction -- in particular, using a round brush and blow dryer on damp hair -- each time you do your hair. Over time, you'll see that your hair starts to naturally fall that way.
You can have your hair cut into longer layers, that's no problem, as long as you part your hair far to one side -- or down the center, if your cowlick lies more to one side. Keep the shortest layers at about chin-level so your cowlick stays covered up, and drape the hair across your forehead, cutting it down in size.
If you take after Alfalfa from The Little Rascals and you have a cowlick at the back of your head, the best way to hide it is to get a bob cut. Particularly an angled bob cut will be more voluminous at the back and angle down to longer pieces on the sides, and hide that cowlick out of sight. Add in some straight across bangs -- shorter or longer will work -- or side-swept bangs to make your forehead appear smaller.