I heard that sticking the onion in the freezer fifteen minutes before you cut it helps. An article I read said that it really works. Try that!
For the garlic smell, either learn to love it, or wear gloves next time. xD
Um, I just read that you wash your hands right after you cut the garlic, rub a stainless steel object [like a fork or something], then wash your hands again. That should work. I should try that, lol.
Another article said to rub the object on your hand whilst under running water.