Be Realistic. Plan on needing a few days to settle into the climbing style. It's difficult to work projects on the road because of time, weather, and other mishaps. Set goals that you can easily achieve and save the projects for your home crag. Completing a route is way better than leaving behind a project.
Sample the climbing- when visiting a new area, whether it's indoors or outdoors, try everything. Trying a lot of routes or boulder problems will help you get a lay of the land, learn what you want to project, and help you get the basic skills of an area. Start small and get in tune with the climbing.
Be flexible. Bad weather, partner problems, and injury can all flip a great climbing trip into a heinous way. The best way to deal with these mishaps is to have a second option of places or styles of climbing. Having more than one goal will help in the case of foul weather. Steep rock will often stay drier in bad weather. Slab routes are great to climb when it's cold. If the weather is nothing like you planned, make the most of the situation and check out formations you want to climb in the future. A little knowledge about where the climb is and what it looks like will prepare you for a future ascent.
Have fun. One of the most important parts of climbing is having a good time. Stay stress free- if you injure yourself and you'll recover faster. It will also make partner situations a little more relaxing.