The two sides of your face are more like sisters than twins, and the same thing goes with eyebrows. Though it's not possible to achieve a perfect double of one brow on the other side (sometimes the angle will be off, or one will be thicker than the other), there are steps you can take to even them out.
Watch this video by Petrilude to train yourself in the art of eyebrow drawing. Using a brow stencil and dark eyeshadow or face powder, you stamp your eye with the powder for an even brow shape. You then fill in the brow with your brow liner.