Depending on the time I have, and how much fabric I'm working with, I will tear, then trim. Most of my stash is in 1/2 to 1 yard pieces. People think that tearing is wasteful, but I find it to be the exact opposite. Make a cut about 1" in, past the selvage. One quick rip. It's very satisfying, lol. The edge usually has maybe 1/4" of loose threads. I press the edge so the loose bits are flat, then use one that is visible to line up my ruler. That's it. After that, my fabric, strips, pieces do not fray or ravel. It makes the backs of tops so much neater - no taking hours to clean up threads before going to the long arm quilter.
People who don't like it say you've wasted a strip, or that it's going to damage the remaining fabric - some claiming several inches. I've never had that happen, and like a clean edge. I'm attaching a couple of pictures. The pink one is a fabric from LQS, cut as it came off the bolt. When I straightened it, using the "normal" method, you can see that I'm going to have to cut quite a bit off to straighten the edge - so not sure how I'd be losing so much more anyhow. Note that I do not hold the shop responsible for fabric that is crooked on the bolt, as in this case. Unless shops are tearing, which most people don't seem to want, you're going to have this happen sometimes.
The second picture is a fabric that I tore and pressed. As you can see, I really don't have to trim much off.