Before painting, I would highly recommend using a primer/paint combo so you don't have to do several coats. This will make things go quicker.
Start by taping off the trim and borders.
We need to determine how wide the chevron stripes will be according to the size of your wall. For my wall, each stripe was 4ft wide.
I used my ruler to mark points of intersect every 12 inches wide and 12 inches high. The points will serve as guides to ensure a straight line.
Don't worry about creating a huge grid. All you need are little points of intersect. We then taped off the pattern.
Now comes the tricky part. You need to mark which areas are going to be painted and which aren't. Then, completely tape off the area you don't want to paint.
Be sure to clean up all corners and double check your work.
Put down your drop cloth and start painting. Since you've completely taped off everything, you can just go for it!!! It is faster that way. Give it about 10 minutes and then peel off the tape.
Once you've peeled off the tape, you should see something like this.