I always trim my own hair and I never let anyone else cut my bangs, but if you're going drastic, please take it to a professional. And not just any professional, scout them out, like whenever you go out for groceries, eyeball nearby hairdressers. You Can and Should judge a book by its cover. Save lots of images of possible cuts, give it a few weeks, and if you still feel strongly, take your ideas to your appointment and let the hairdresser explain pros and cons of each style. I always operate on the side of caution, because it takes me a good four years to grow mine out.