Have a servant mentality. "Mission…must take the form of servanthood. Only in this way can it escape the charge of arrogance." –G. Thompson Brown
See yourself with a towel draped over your arm, regardless of who you are or what you do.
A missionary wrote about a team of doctors on a mission trip who complained that too many patients were showing up, and that they were working too many hours without enough leisure time. They made faces at the food they were served. They also called the local pastor's wife a liar and pouted when they didn't get exactly what they wanted.
Do you smell the arrogance and see the irony? The ones supposed to heal the sick and bind the wounded instead spread disease and inflicted injury with their self-serving attitude.
To have served humbly would have quenched their incessant demands. In the end, the pain the nationals experienced remains greater than any good that occurred.
Bathe the trip in prayer. "Devote yourselves to prayer with an alert mind and a thankful heart. Pray for us, too, that God will give us many opportunities to speak about his mysterious plan concerning Christ" (Colossians 4:2–3).
More than a suggestion, prayer is a necessity on so many levels: spiritual anointing, physical protection, emotional endurance, mental strength, and team unity.
The most fruitful teams we've led and received have been teams dedicated to prayer and fasting, both before and during the trip. Also vital is having a prayer-support group interceding back home while the team is on their mission.
The Word of God, in whose name you travel, gives numerous examples of what can happen when we meet before his throne. From Moses' intercession in Exodus 17 to James' reminder of the effectiveness of the righteous man's prayer, we can be assured God hears and moves in response.
Learn to adapt. "No matter how adept an exegete a theologian is…it is all for naught if he does not understand his contemporary audience." ¬–Dallas Willard
Jesus had 30-plus years to grow in his surroundings; you'll have one, maybe two weeks. How are you supposed to adapt in that short time? You won't really, but something that can help is trusting your host and/or the nationals with whom you'll be working. Take cues from them and it will go well with you.
Investigating the culture and specific people group before you go will also be a great asset. You won't learn everything, but you will have opened the door to understanding, an important aspect of communication.