Let's
make these 4 patches with black fabric for two of the patches, and
a different pair of solid or marble fabrics for the other two.
I
think they'll all fit together and be more useful if we don't
have a huge variety of fabric types.
You
can make as many as you want. At the guild meeting, we'll gather around
a table to trade squares, and you'll leave with as many as you came
with, but in a range of colors.
If
you prefer, you can cut a bunch of 2 inch squares, half from black
fabric, and half in at least two different colors. Sew them together
to make your 4 patches.
The
4 patch will finish at 3 inches, so the ones you bring to swap should
measure 3½ inches, including seam allowances.