Tire pressure need help

Subject: Correct tire pressure
I have read every thread on the tire forum and I am completely confused !

I have a 2002 TM 3023 with 15" Goodyear tires.
TM instruction manual stating tire pressure should be 65lbs/sq inch

In two weeks I am heading out from League City, TX to Denver (1100miles)
Simple question what should my tire pressure be when I pull out of my
driveway @ 05:00 May15th 2006 heading out to Denver.
How often during the trip should I check the tires? What should I look for?

Your help/guidance needed.

Thanks
John Zwart