One of my 35 before 35 goals was to fill a journal up with collages. I'm on my way.
For me, collage is just a way to unwind and play around. I try not to think about it too hard. Yet, it's a fun puzzle - cutting out pieces and moving them around until they start to feel right. Eventually I say good enough, turn the page and start the next one. It's a low pressure way to play around with style, techniques and composition. And believe me, that experimentation leads to pages that are disasters and that I would never post on the internet!
Katie Licht is a collage artist who inspires me. She is an illustrator, a graphic designer and a Midwesterner too. I bought two of her art journal packs and they are really affordable and great collage starters. She also recently made her own zine which is super fun! She includes tips to get you started with making your own book of fun, vintage inspired collages. She didn't pay me to say this or nothing. Just someone whose work I recommend checking out if this is your thing.