First, you need to determine the size of blocks you want to make. I wanted 4" finished blocks so I could easily make them work with a 16", 20", or 24" pillow form. You'll need to adjust the size of you paper if you want larger or smaller blocks.
Start with a 4x4" piece of paper. Line your paper up on your cutting mat and then begin drawing the following lines by rotating your ruler around the square.
Top left to bottom right - one inch in from both sides:
Top right to bottom left - one inch in from both sides: (this image also shows my drawn line top left to bottom right of one inch down and one inch up)
Top right to bottom left - one inch down and one inch up:
Your finished block should have four criss-crossing lines on it and should look like this:
Next, align your ruler with one of the drawn lines (it doesn't matter which one), and cut the square into two halves.
Then, paper piece your desired fabrics onto one half of the paper. Since we used a 4" square, which is our finished size, make sure you have plenty of fabric on the outside edges of the paper for trimming. For paper piecing basics, check out this post or do a web search for "paper piecing" (not to be confused with "English paper piecing") - there are plenty of posts and videos out there to help you if you've never tried paper piecing before.
Repeat with the other half of your 4" square.
Now it's time to square up both halves. Place your 1/4" mark on your ruler on each edge of the paper and trim. This is your seam allowance.
Each trimmed half should look like this:
Align your two halves so the long diagonal edges of each paper match up, right sides together. Stitch just along the edge of the paper. (Sorry, I forgot to take a picture of this.)
Press your seams and remove the paper on the back. Here's what your finished block will look like:
You can then repeat the above steps to make as many blocks as you like. Arrange the blocks as desired. Sew the blocks into rows and the rows together to make a pillow or quilt top.
For my PTS9 pillow, I made 16 blocks and laid them out in a 4x4 layout. I then added a thin white border and then a thicker border to achieve my desired pillow top size.
I was really pleased with how this pillow came together. I really want to make a quilt using this technique, but with larger block sizes. Perhaps that's something to put on 2013's to-do list.