<3 how can i make my hair wavy?

my hair is nautrally in between straight and wavy, mostly straight with a bit of a wave, thick and long (it goes to the bottom of my .) i wanna make it really wavy and pretty without using a curling iron or rollers, just a product like some kind of curl/wave forming mousse or something like that. i've tried sunsilk captivating curls scrunching mousse but it didn't work on my hair, i know there were lots of amazing reviews for it but they all had curly hair already and my hair is too straight for that. what products would you recommend? :)