The four patch block is one of the simplest pieced quilt blocks. It is made by sewing 4 squares the same size together to make a larger square. Four patch blocks can be made using 2, 3 or 4 different fabrics depending on the effect you are after.
The 4 patch block is a good starting place to make sure your 1/4" seams really are 1/4" and to get to grips with learning to align seams where they meet. In this instructable I also show how to press your seams in opposite directions so you don't get a big lump when you sew the sections of the block together.
Step 1: Requirements
or needle and thread if you hand piece (i.e. no sewing machine)
Rotary cutter (not absolutely necessary, but makes cutting squares much faster)
My sewing instructions will all be for machine piecing, but the basic idea, cutting, pressing and layout are the same for hand piecing.
Step 2: Sewing the Block
Sew along one edge with a 1/4" seam.
Repeat for your other 2 squares.
Step 3: Press the Seams
Put your pairs of squares on the ironing board with the darker fabric on top and then place your iron on the seam and press the iron down on the seam for a few seconds without sliding the iron around. Remove the iron from the fabric and press the seam of your other pair of squares the same way.
Now open the squares up like a book by folding the dark fabric over the seam and press it back in place, again try not to slide your iron about more than necessary as this can distort the fabric. You want the fold of the fabric to be as close as possible to the stitches.
Step 4: Finish the Block.
Sew a 1/4" seam down the right hand side of your squares. When you get to the seam feed it gently under the foot so that it doesn't flip and try to keep the seams butted right up against each other.
Take you sewn block to the ironing board and press the seam flat, then open as before (you can't only press to the dark side this time) and there is your completed 4 patch block.
Step 5: Note on Sizes
...for a 4" finished block ( 4 1/2" unfinished) your squares need to be 2 1/2"
...for a 6" finished block ( 6 1/2" unfinished) your squares need to be 3 1/2"
...for a 8" finished block ( 8 1/2" unfinished) your squares need to be 4 1/2"
...for a 12" finished block ( 12 1/2" unfinished) your squares need to be 6 1/2"
Hope that helps!