Step 2: Getting started
Take 1/4 of each color( The clay is already divided out for you, just cut along the lines), except for Black, which you will need 1/2 of one bar.
Use your roller to flatten these little pieces out and place them next to each other, overlapping a small amount. It doesn't matter in which order you place the strips next to each other, because it will be completely blended by the time you are done. Fold the clay over horizontally ( so that the colors lay against themselves) and continue rolling until you can start to see the colors blend.
At this point you can determine if you want to keep this blend, keep going, or fold it a completely different way to get a different color. Here i folded it Vertically, and kept rolling, changing the fold ever time until I got something that i liked.