In order to get a good night’s sleep, you need to sleep in complete darkness. If there is a street light outside your window shining into your bedroom, you will sleep much better if you get light-blocking drapes. Use night lights with red bulbs so if you need to get up to go to the bathroom, you can do so without turning on the lights, which would result in the shutting down of your sleep hormone melatonin, making it harder to get the rest you need. Our bodies are very sensitive to light, and any light shining on any part of our skin makes our body think it is morning, resulting in the hormone cortisol being released to help give us the energy we need to begin our day. This is not the best situation if it is 2 AM! So go to bed turning out the lights by 10h30pm at the latest, sleep dark and sleep well.
For more information on the effect of light and our sleep patterns, please enjoy the book Lights Out! by Formby & Wiley.