This can create a more dramatic effect by choosing a beanie the contrasts your hair color. For dark hair a light colored beanie, and a dark beanie for lighter hair. Some beanies can be little more slouchy. Slouchy styles are simply great for giving you that cool off-duty appearance. Simply wear your beanie shoved back on your head while leaving the back of your beanie loose and slouchy.
If you have short enough bangs, you can let them hang straight down over your eyebrows. The beanie will flatten your bangs out, though, so this style tends not to work if you have longer bangs that would come down over your eyes. It also works best if you have long hair rather than short or medium hair.
Pull your hair towards the front to get a kind of 70s look.
It is quite stylish to pull your curly hair back so the beanie pulls down over your forehead. Then let your curls release playfully from the back of the beanie. You can also pull the beanie behind the scalp line to create an attractive tangle of curls with your bangs. If you are trying to contain the curls try a head wrap to hold your hair close to your head with a beanie pulled down over the top of the wrap. Neither the wrap nor your hair would be visible.
Choose neon colors if you are hunting or otherwise participating in winter activities that require you to be very visible. If your hanging around in a coffee shop, or going on a date leave the neon colored beanie at home. Neon colors are generally appropriate for practical rather than fashionable purposes.
If you put a lot of time into your hair make sure you have some visible. Remember though the beanie might unsettle your hair if you normally wear it with out product, so it is perfectly acceptable to cover the entire top of your head with the beanie.