Self soothing confusion

Lindsey
Ok, so my almost 4 month old is now refusing and fighting naps so badly. She kicks and flails and cries when she can tell it's time for a nap. Sometimes we spend HOURS trying to get her to sleep.
My question is how do I help teach her to self soothe without letting her cry it out? I don't want to take that approach with her. We've tried it once and it was horrible for us both and didn't work.
I'm beginning to obsess over how to get her to nap, fearing over sleep crutches, and worried I'm setting us up for failure in the future. Please help!