I try to always use leaders/enders. Right now I have a small basket of 2 1/2" dark squares and one of light squares. While watching TV, I match up the darks and lights, right sides together, then stack them turning 1/4 turn each time. I keep a stack by my sewing machine ready to be used. Once I get a stack done, I'll press them open and, again while watching TV, I'll stack pairs read to sew into 4-patches.
There are a lot of patterns that use 4-patches and I LOVE scrappy quilts. So this is perfect for me. However, if you are planning to do a quilt that calls for 2 color 4-patches, you could do the same with them.
Here is a link to my scrappy Double Irish Chain I pieced with 2" leaders/enders squares
http://www.quiltingboard.com/t-95998-1.htm.