OK, here are the instructions I promised. This is the one most people like because it goes faster than hand sewing.
1. Cut four 7 1/2" muslin squares.
2. Fold each square in half and stitch a 1/4" seam, from the folded to the raw edge on one side of the rectangle and from the raw edge to the folded edge on the other side.
2. Trim corners of stitched rectangles.
3. Fold the seamed edge of each rectangle to meet the opposite seamed edge, right sides together. Place a pin where the seamlines meet.
4. Stitch the folded-upon-itself rectangle, leaving a 1" opening for turning.
5. Taking care not to stretch and distort the fabric, turn the square inside out, shaping and sharpening the corners. Press the square carefully since the straight edges are now on the bias.
6. Turn one corner to the center and press. Repeat with remaining corners.
7. Place 2 squares wrong sides together and sew across pointed flap on the pressed line.
8. Put 2" colored square on top of diamond formed in the last step. Turn edges of diamond over square and top stitch.
9. Continue adding squares until quilt is desired size.