Wave help!!!

I have hair that naturally has a little bit of wave in it, but I usually straighten it because it's not so much wave that it looks good, it just looks really messy. But, I want to make it wavy like Lindsay Lohan's or Ashlee or Jessica Simpson. I've tried everything, hair gel, moouse, curling irons, braiding, and everything, but curling irons just WON'T curl my hair, and braids don't get the effect I want. I've tried rollers too. Can anyone help me?

u should try this after washing ur hair flip your head over and apply gel starting at the nape of ur neck making sure to scrunch evenly throughout hair roots to ends. Repeat. usind a blow dryer with a diffuser, dry hair in one-to two inch sections scrunching it with your hands as it dries. this way the blow dryer heats the curl while the scrubch sets it. make sure that all your hair is fairly dry, but not bone dry. I hope this helps