First things first. . . pick a couple of paint colors, test them on your walls in the "real" light, and then buy the best one. Make sure to document your paint color and to save a small amount of paint in a jar for touch-ups. Painting is not difficult, but it helps to know what you are doing. Read over some "how to paint" basics if you are a first time painter, and then consider these added hints:
1. Use a hammer and nail to make small holes around the rim of the paint can. This helps the paint drain from the edges instead of pooling and leading to sticky paint lids.
2. When you are ready to close the paint can, cover the it with a plastic bag and then hammer on the lid. This will also help prevent the paint from drying and sealing the lid closed.
3. Use a paint edger rather than a paintbrush to neatly cut in around the trimwork. This almost eliminates the need for taping the trim and the pads for the edger are disposable.
5. Roll out craft paper around the perimeter of the room and tape it down. It protects your floor from splatters and is easier than those crawly drop cloths.
6. When you are done painting for the day, wrap your tools in plastic and cover the paint tray with plastic wrap. Everything should stay wet so you can pick up where you left off the next day.