First of all, decide what kind of bang you want. Personally, I love the heavy bang, commonly referred to in the 5th grade as the pie shaped bang. Usually when I try this, I get a wispy Helen Hunt bang, or at best, a bad feathery Claudia Schiffer bang. However, bangs I covet most are Melissahead Yabberings, Heidi Klum bangs at times, and for a minute Zooey Deschanel's bangs in 500 Days of Summer. Oops, if you look at those, 2 out of 3 have dark brown hair, which may help the bang look more solid instead of whispy.
Here is how to cut your bangs at home:
1. Wet your bangs. It's best done right out of the shower.
2. Use sharp, pointy scissors. I was in an emergency, and used scissors from Sephora that are curved at the top. This is not recommended, but will suffice in an emergency.
3. If you have long bangs (aka, no bangs), comb down the amount of bangs you want. If you want the pie shaped bang as mentioned above, you literally should pull down your bang in the shape of a triangle, with a point of center up at the top. Don't make the bang all straight accross at the root. Make it in a triangle shape.
4. This is the fun and scary part. You need to cut off several inches. Hold your wet hair straightly between your fingers, and start cutting accross (the result of this is shown in the picture above. You can cut straight accross, or at a sharp diagonal. I did a sharp diagonal just for fun, leaving one side almost long enough to go behind my ear. Leave room for error, so cut it slightly longer than you actually want them.
5. Now trim the line you just cut. Hold your scissors at a vertical angle, and cut up into the bang. Don't cut horizontally anymore. Cut up. This will give some dimension to your bang, and help it not look like such a jagged edge.
6. To style, put a bit of mouse, or my favorite, the mens Texture Creme from Crew. Love that stuff. That will add some body and lift your bang.
Things to think about in the morning:
1. If you are a two-day hair kind of girl, note that your new bangs may very well stick straight up in the morning. They will probably calm down, but won't have that 'just stepped out from under the blow dryer' effect.
2. You may want to make them shorter, because they will suddenly be in your eyes. Pause before doing this because you are about to really mess them up, and then trim. When you trim, continue with the vertical angle on the scissor. This will take a longer time to actually trim your new bangs, but is less room for glaring error. You'll still have error because you did it yourself, but it won't be so, so bad.