Wavy hair problem

My hair is about an inch above my shoulders, and is naturally wavy, especially in the front. I like to blow it straight, but it doesn`t last if I go swimming, or if it`s humid in the summer. I wish I could just scrunch when I blow-dry, but since the waves are uneven throughout my hair, it doesn`t always look right. I wish I could make the waves have a little more body and separation. Would cutting some (but not too many) layers into my hair make the waves bounce up? Are there any hair products that would help me achieve the separated look that aren`t too heavy? Thanks a lot!!