Dianne asked what ruler I use to cut my triangles. It all depends on the scraps I'm using I suppose.

Recently I went through the 2 1/2" strip drawer and weeded out some shorter lengths to make a bit of room. I cut these up using the Easy Angle, which makes quick work of this chore. I cut a heap of light strips too, but I obviously need more...

They get stacked on a small tray and that lives on a shelf next to the sewing machine, just in case I need an emergency leader-ender pair. (I usually have some specific project for a leader-ender, but I've been known to run out of cut pieces.)

If however, the scrap isn't a strip or is an odd shape, I really love using the ScrapSaver by Judy Hopkins.

 Sadly, Judy died in 2011, but it seems that you can get the ScrapMaster which is almost the same from here. I get a lot of gifted scraps, and I've used this over the years to easily cut them into usable shapes.

These were some triangle offcuts from a TriRecs ruler or something like that, so the angle wasn't 45 degrees.

By placing the ruler over them I can see that I can cut a 2 7/8" triangle with a little bit to spare.

I make the first cut along the edge of the ruler,

then I turn it around and reposition the corner of the ruler over the scrap, making sure that the 2 7/8" line is on the previously cut edge

 and cut the 90 degree angle.

Sometimes I think a scrap is too small to use, but I can see straight away whether I can get a certain size triangle from it.

Dianne also mentioned the dog ears, but they don't worry me. When I've sewn and pressed a heap of triangles I get a cup of coffee and a small pair of  sharp scissors and by the time I've finished my drink I've trimmed all the pointy bits off. I don't like making HST oversize and cutting them down- I find that I sew accurately enough (after thousands of seams!) to get the results I want first time around.

 (But if the cutting down works for you, that's fine too. We all have our own methods of working...)