Also, if you do encounter bogeys, don't attack them head on. Kite them around, then slice them in half one by one. After beating the first wave, you can sleep safely for the remainder of the night, provided that you don't move on the map. I think. Don't blame me if they do attack a second time, though. Or, better yet, spend the nights in houses/with companions.
Otherwise, do as freeformschooler said (and get a shield, because no shield + dragon = you have deceased) and avoid night beasts to begin with. They're notoriously difficult to kill on your own, and even with companions can absolutely decimate you. Once you become legendary though, you'll be chopping them in half easily. :U
Bandits are much better for getting that initial training, since they're both fairly managable and numerous. Their leaders can be tricky, since they're often damned good at dodging, but as long as you get in the first hit, you should be fine.
Also, SET CHARGE DEFENSE TO DODGE. It's no big deal if a small enemy bumps into or rushes by you, but getting charged by something massive (i.e. a titan) could easily become your doom. And at the same time, don't charge said massive opponents. More often than not, you'll be knocked down. It's very effective to do against enemies of equal or smaller size, but bigger enemies can be like running into a wall. A large and angry wall of muscle/blubber with teeth and/or weapons.
Oh, and kill ranged enemies quickly, or stay behind a tree. They will hit you eventually, and you should assume that it's going to hurt.