I've never really been good friends with my brayer. But maybe it's fair to say now that we're pals. Doing these colorful brayered backgrounds is a trial and error thing. You've gotta have the right sort of paper, a bit of patience, great inks and images to work with, and a willingness to experiment.
Take five to check out this video so that you can see how it's done.
Here's the other bummer. The stamps that I used on this demo have already sold out! But don't fear. . . for now, this sheet is still available, and it will work beautifully. And wait 'til you see the Club Stamp sheet coming out on the 20th!!! Oh, my, heavens.