This advise comes from my delivery nurse. And it helped a lot.
She gave us the advise to put red bulbs in the lamps. So we had a lamp with a red bulb near the baby bed.
Before your baby was born everything looked red for your child in its little world inside of you. This red light gives your baby safety and can help to sleep better.
And another great thing is when you have to go to your little sunshine during night you don't have to switch the lights on, you can see everything around you with the red bulb.