Valley of the Gods is an awesome spot for boondocking. The road through it isn't too bad unless its rained recently. Watch your trailer clearance on the dry wash crossings. This or a flat tire will likely be bigger problems than sand. As others have mentioned:
Airing down is the best solution to avoid getting stuck in sand (I drop my Tacoma to 15 psi on the NC beaches) and it can also help with ride quality on washboard roads but ONLY if you have a good 12V compressor. The cigarette lighter types for $25 won't cut it. Plan to spend $75-$150 and get one with alligator clips that connect directly to the battery. ViAir is a good brand. Make sure your spare is fully inflated and it and your jack are good condition. A 12"x12" piece of plywood provides a more stable jack base. Take a reliable air gauge. A quality tire plug kit is also a plus IF you know how to use it. At least two thirty foot tow straps (no metal hooks on the ends) are a good addition to any recovery kit.
Do not attempt the Moki Dugway on the western end with your camper. It is an awesome drive though with just your vehicle.
Take extra water just in case. And have fun, its a beautiful area and I'm looking forward to pictures and a trip report.