I did this for a lot of years, so it might not work as well for you, but I used to comb gel through my hair, comb it straight, then comb out the crunch when it got dry. This really reduced the amount of wave in my hair. I also live in Las Vegas and have really short hair, so this method didn't cause frizz, but might not work as well in humid areas or with longer hair.
Experimenting with too many products to name here. All this great info keeps my head spinning.