I did a long cross country last summer all VFR from Pompano, Florida (KPMP) to Taunton, Massachusetts (KTAN). I was with a friend of mine and here are my reccomendations:

1. Like Ewfflyer said, get flight following.

2. Check your enroute weather. When i was on my trip, we hit some weather in Virginia. All we saw from the air was some low clouds. We tried to get under them and maintain VFR, but was unable. After landing we found out there was a huge cell just ahead of where we were trying to go.

3. Check your special use aircpace along the route and ake sure you know which you can penetrate and which you cannot and how to find that information on your sectional.

4. Stay hydrated and sharp. If you feel like you need a break prior to your next planned fuel stop, just land and take a break. And although after that lojng flight, your going to feel like a king in the aircraft, do not get complacent. An airplane can humble you in an instant.

And most of all, have fun and enjoy the scenery and experience on the way out and back!