1. Binoculars or telescope(don't forget the eyepieces) or just your unaided vision.
2.Star map, you can get one at skymaps.com 
3.A red light. Why red you might ask; well red light helps keep your night vision. If you use a white light it could take up to 20 minutes to get your night vision back.
4. If it's summer, bring bug spray and I repeat bring bug spray. If it is winter be sure and dress warm.
5.Plenty to drink.
6.Last but not least bring a chair. The more comfortable you are the more you will see and the more you will enjoy it. Comfort is everything.
Well that is about all you will need to start observing. The key is to learn the constellations in the sky then look for the harder to find objects.