These triangle borders are slowing me down, I just can't get motivated to tackle the measuring and attaching of them.  I cut and sewed them with no trouble, but I can't get enthused about the calculating and fudging the next step will involve.

 They measure 2" on the long side, which needed to be on the straight grain of the fabric.  I cut 3.25" squares, then cut them twice diagonally to give the right size triangles.  I added an extra step to make aligning them easy.

Before I moved the triangles I aligned the 2" line of the ruler to the diagonal cuts and trimmed off the dogears in situ.

I did that on all four sides, and that gave me really accurate results when I pieced the triangles together.  A rotating cutting mat would make this super easy, but I was too lazy to find mine so I just moved around to get in the best position to make those cuts.

Getting rid of the dog ears made it so easy to line up the triangles, so that there would be a nice straight edge when they were sewn together. 

Trimming them all at once was so much easier than working on each stack of traingles after they'd been moved.

 Next time I need to make this sort of border I will be able to refer back to this post, which is a good thing.  I just know that in a few months time I'll forget what I did.  I just hope I don't forget that I wrote this post :(