How to Style Thick Wavy Hair?

My hair is extremely thick, and also sort of wavy (not curly). When it gets 3-4 inches long it turns very mop-like, and whenever I apply any product like gel or putty it just flops down after like 30 minutes and appears more wavy, ugly and unkempt…I've tried straightening, doesnt really work very well since I cant get to the roots or section off my hair its so thick..are there any products/ways to get a cool style? n.b. mens hairstyle

Suggestion:

If you're having daily trouble styling your hair, you might want to try something stronger than daily straightening. Have you heard of keratin treatments? They're really easy and only 90 minutes to lead your hair to it's best state. Your hair will be more tamed, healthy and glossier. Most importantly, your hair will be easier to style because you'll have more control over it. The best treatment I know of is Brazilian Gloss. I'll link their about page and try it out you won't regret it!