Fans or other white noise generators near the bed can help mute sleep distractions. A cheaper alternative is to set the tuner of your FM radio between any two stations. The pseudo white noise you'll hear will do wonders to mask unwanted sounds.
Light Level
Use room darkening shades or dark fabrics to reduce the amount light leaking into the room. Eyeshades may also do the trick.
Temperature
65° F is the ideal temperature for sleeping. A warm room or too many blankets can interrupt your sleep.