I personally like doing half square triangles but making the squares and drawing a line in the middle and sewing two lines 1/4th from each side. That's just me. I tried triangles on the roll, it's nice, but having the tear out all that paper was never really that fun to me and it seems like one more step till getting to ironing.
Well here's the website that shows you why adding 7/8ths to any finished half square triangle using my favoriate method of doing it works.
I love how neatly he laid it out and the pictures help lots! ^_^
If you like the grid paper method (triangles on a roll) and you don't have triangles on a roll or can't get them for some reason or need to do what you need to do now. I found a website that has 1", 2", 3" and 4" printable grids.
Here it is
It's on the bottom of this website.
To let you know though. A long time ago I tried photo copying some triangle on a roll that Holly gave me because I needed a few extra squares for a side project and The Granery didn't have the size I needed so they suggest just photo copying the ones I haven't used yet (since I was showing them the sample I got from Holly to buy it). Trying to just use regular printer paper to do the triangles on the roll method = bad idea. I would just have been better of waiting for the triangles on the roll to get in rather than dealing with printer paper version of it. But like I said if you're in a bind you can use this.