Pattern inspired by a quilt I saw. Mostly solid color granny squares with a few two color granny squares that look like 2 triangles. To make the two color grannies I used the pattern linked above. Since I make most of my grannies turning after each round, this tutorial made the most sense to me.
Simple sc border (back loops only)
2 sc in each corner stitch
In the 2 corner chains, where 2 squares are joined, I double crocheted 2 together. This extra height helps straighten the edge.