Thank you! It really is easy; easier than I thought it would be from the instructions I had, even.
First, I took a piece of white cotton fabric cut to the size I wanted. I ironed it and then stitched all around the edges so it wouldn't fray up later. I lightly drew a simple outline on the fabric with pencil. I used a plastic cutting board to put the fabric on so that if the glue went all the way through too much I could peel it off.
I then traced the pencil marks with a thin line of Elmer's Gel Glue (the thinner the line, the more careful you have to be when painting it), it's blue colored and I bought it at Rite-Aid. At first I didn't think it was going to soak through the material enough to keep the paint from bleeding through, but it really did. I let the glue dry over night. A few hours probably would have been enough, but I did it in the evening, so it wasn't dry before I went to bed.
After it had dried the material seemed a little puckered from the glue, but that came out in the washing process.
I used slightly watered down acrylic paints, but depending on what you're going for you can use anything that doesn't wash out in water. I'm even thinking that crayons would work. At first I watered my paint down too much and it just ran through the fabric. That would have been fine if I just wanted to color the whole thing a solid color without any detail, but I had to thicken it up for the details.
After it dried completely I filled my sink with warmish-hot water and let the glue soften up. Then I just started scraping the softened glue off. The instructions I read said to then wash it in the washing machine, but I don't have my own washer and the laundry mat where I go only has multi-load sized washers, which I am not going to run just for one 9 x 11 piece of fabric. I just scrubbed it with my fingers until it didn't feel gooey/sticky anymore.
I then laid it out flat to dry again. I didn't get every bit of glue off, which I'm sure would have happened in the wash. After it was dry again I put it in a frame and took a picture.
If my thoughts aren't clear to you, just google "glue batik" and you'll come up with lots of other tutorials. The first one that comes up is for white glue, but I don't know how well that will work. I guess if you do it fast and don't get it too wet, it can hold up long enough for the dye or paint to dry, but I don't think it would have as crisp lines as the gel glue has.