I don't know when I learned to make them but I could create quilts from half square triangles for days and days. I cut the squares a little larger than needed and have more waste than many but in the end, I get blocks that are perfect.
I have tried a few different techniques and even had a roll of the triangle paper at some point but I keep going back to the basic technique. I cut my two squares one inch larger than I want the block (5.5" cut squares will give me 4.5" half square triangles that fiinishe at 4"). This weekend I cut and cut and cut and did a lot of chain stitching and now I think I have enough triangles to start putting together my zigzag quilt. The question remains - off set or lined up?