ON the side of the tires it will give the minimum tire pressure needed in the tire to carry the maximum allowable design weight. Inflate your tires to this pressure until you can get the coach weighed. Once you have the front and rear axle weights, then you can use the manufacturer's tire chart to adjust your COLD tire pressure to the weight of your coach.
Make sure that you weigh the coach with it loaded according to the way you will travel most of the time with a full fuel tank and all passengers. Maybe a half full fresh water tank also.