First lay all your frames together and get a rough layout.
Place all your frames on a white plastic tablecloth (usually $1 or so) you could also use craft paper or anything that is large enough. Measure and get the frames even. Sharpie around the frame edges. Position the table cloth on the wall (I used thumb tacks, but some may prefer tape). Step back check it visually and with your ruler/level. Once it is where you want it begin placing your hanging screws.
This is the second house I have used these frames in. First house I tried to hang one frame then measure off of it to hang the next. Wound up with dozens of holes in the wrong places. This method I had zero errors! Now to update all the photos…..