I am having a little trouble finding the straight of grain. Usually I just fold the fabric so the selvages meet, then adjust by moving the fabric layers to the left/right of each other until the fabric hangs straight at the fold without a twist or wrinkle. Then I trim the cut edges by cutting them at a 90 degree angle with my ruler and rotary cutter on the cutting mat. Never have a problem with anything coming out wonky.
However, always looking for a better or more correct way to do things, I thought I would try pulling a thread across the width, but it kept breaking after about an inch of pulling so I gave up.
Then I tried tearing the fabric along the width which worked beautifully. I ironed the torn edges, folded the fabric, lining up the cut edges, and it lay perfectly flat - success!
But the selvages didn't meet! They met on one side but were 1/2" apart on the other.
On top of that, the design (a floral stripe) was really crooked parallel to the torn edge, but was almost perfectly straight at a 90 degree angle to the selvage.
I'm so totally confused that I'm sorry I ever tried to do it the "better" way.
What would you do? How do you find the straight of grain?