The Brioche Stitch (or combination of stitches) creates a pretty, flat, double-sided fabric. The video below demonstrates both the one-color and two-color Brioche Stitch. Written instructions are available as a free Ravelry download.
EDITED TO ADD: I get a lot of questions regarding fixing mistakes in Brioche Stitch. Here is a common question, plus my answer below:
Q: Staci, I’ve made a mistake in Brioche Stitch, and I’ve ripped my work back so that I can correct the mistake. I’m having a problem getting the stitches back on the needle. Can you help?
A: Sorry you’re having trouble! Yes, it is very difficult to pick up stitches in Brioche Stitch after you’ve made a mistake, even for an advanced knitter. I recommend that you thread “proactive” lifelines in your work every few inches or so, so that if you do have to rip back, all of your stitches (including yarn-overs) are safely held on the scrap yarn, and easy to pick up again.
It sounds like you’ve already made a mistake. The best thing you can do is to rip back below the mistake, and do your best to pick the stitches back up again on the needle. I’m sorry, there isn’t much more help than this I can offer you without actually helping you fix your work in person. You might also try visiting your local yarn shop for help.