You need enough for 4 squares that are each 6 inches. They can all be different designs, the same or anything in between. Trace a template with PENCIL or use a ruler. DO NOT use MARKER ON FABRIC. Measure and cut on the wrong side of the fabric. The neater you cut your pieces, the easier it will be to sew them together.
Lay out and align your pieces to visualize your finished pillow. Right side (good side) facing up.
Work in sets of 2. Sew each pair together by closing the two squares like a book. They should be laid on top of one another with the right sides together.
Line up the fabric along the edge you will sew. Use 2-3 pins to secure the fabric. Pins should go down through both layers and then back out through both layers.
Sew the 2 squares together along the pinned edge. Choose a seam allowance between 1/4" and 5/8". Use the same seam allowance for the whole project. Backstitch all the way to the top of the fabric and sew all the way to the other end as well. Take out the pins as you go.
Open both pairs of sewn squares. Lay out your pattern so it is correct. Close your two pairs along the side you want to sew together. Pin in place and sew together.
Using the diagram as a guide, sew your pillow together. Use a 5/8 seam allowance (line the edge of your fabric up with the 5/8 line on the baseplate). Remove pins as you get to them.
Flip your pillow right side out. Use your fingers or the eraser end of a pencil to square out your corners. Check for holes along your seams as you go. Fill your pillow with stuffing!
Use a hand needle and thread that closely matches your fabric (not the high contrast thread I use in my demo). Use a whip stitch to sew your pillow closed by hand. Cut a piece of thread that is as long as your wing-span (hand to hand with your arms outstretched). Thread your needle. Even out the two threads. Tie a knot on the opposite end of the needle. A whip stitch always goes in the front and out the back. Keep your stitches small and close together.