Some find it easier to handle the strips by sewing them into pairs, then the pairs into 4's, etc.
One reason behind this is to keep the sewn strips from becoming bowed. But there are ways to avoide this :wink:
PRESS, do not iron the strip's seams, press each area once, and never move your iron back and forth across them.
When you sew the strips together, alternate which end you start from. If you start sewing from the same end each time, the strip sets may start bowing.
The purpose of sewing the strips all together first, is to make a big "sheet of fabric"
Then you cut these sheets up into the correct sized strips to form your design.
Then when you cut out your strips from this, it is easy to cut them one inch or more. You will be cutting across the strips, so each cut will include each of the strips that you have sewn together.
You can cut the individual fabrics into small pieces and sew them end to end, but sometimes these pieces would end up being one inch wide and hard to handle. So someone came up with the idea of "strip piecing" them, to make the process go easier.