Generally, You can wax, shave, trim, and use hair removal cream, if all else fails you may want to see a professional. Trimming with scissors is what I would do personally, and you will have to use the aid of a mirror.
This is a common complaint for women. Fortunately, this problem can easily be resolved. For as little as $15.00 at most salons, you can have a professional who specializes in eyebrow waxing wax your brows. It involves very little pain, and is very fast. The aestheticism will teach you how to maintain your new look in between waxings.
You could use an eyebrow trimmer with an attachment. It will thin them out. You could also wax or pluck them to remove some from the top and or bottom.
There are three methods: waxing, trimming, and tweezing (also known as plucking). If you are a beginner, you can use eyebrow templates from the drugstore to get a nice shape.