Step 1: Measure from the outside of your nose straight up to find out where your forehead should start. “This creates a slimming effect on the bridge of your nose,” says Reid.
Step 2: “Then, find where your forehead is naturally at its highest by following a diagonal line from the outside of your nose across the center of your eye,” says Reid. This is where your arch should be. If you’re having trouble finding your arch Kelley Baker, famed brow expert, says that as a general rule your arch should start on the outside of the iris of your eye.
Step 3: According to Reid, you can find the end of your forehead by going from the outside of your nose to the outer corner of your eye.
Step 4: Mark each of these spots and then sketch a few lines to connect them at the top and bottom of the eyebrow. “Hairs that fall outside these lines are your hair should remove at the tweezers and those that are inside the lines should stay,” says Reid.