Art journaling is one of the best, healthiest, creative habits that I've found.
It can be as elaborate or simple as you want.
In this journal, I've used simply ink.
(I branch out, using a lot more color and layering, in some of my other journals.)
I write, doodle, sketch things out, while I'm waiting in lines, riding in the van with my Man, or watching the kids play outside.
First, simply get something to draw/write in. Don't have the money for Smashbooks or scrapbook sets? Not a problem. My absolute favorite art journal is one that is heavy enough to add paint or sharpies to, but not so thick that it's bulky. The spiral bound is a big perk, too, as the journal will lay flat while in use. Plus, this enables you to work easier across 2-page spreads. (That link goes to the exact journals I buy, from Amazon.) It's a mere $9-ish and will last you quite a while....BUT if you don't have the money for that, start with printer paper, a notebook, or even an old used journal. Or, heck, use a napkin.
but sharpie pens...or just about anything else, will work fine, too.
There's really no excuse to delay starting!
Don't forget to capture the lighthearted, goofy moods as well....