Tailoring my jeans smaller Sewing Machines Parts and Sales in Los Angeles

I can do basic sewing, follow patterns, even mix patterns a little. I want to tailor several pairs of pants after losing a couple sizes. I feel confident about shaping the hips/legs, but the waist band on the jeans is really thick. It’s at least 2 layers and I can’t just fold and sew. All the YouTube videos I’ve found are that kind of simplistic method. Any suggestions for working with a very thick fabric?

If I screw up horribly it’s ok. I can just buy more pants, but I love crafty projects and want to try.