I find sand hard to judge. Not just how soft but how deep. I would tend to go 'all-in' with 4LO and moderately high speed to carry you through. Look for other tire tracks to guide you. If you go in too slow or just 2WD and get bogged down it is even harder to get moving again even if you dig some, engage 4wd and air down the tires. Slight inclination is much harder than anything level or down. Go at an angle if you can. If you meet someone on the trail... stick together for the difficult parts. Best of luck.
Soft like dry sand on an ocean beach is about max. Some desert sand is very fine blown in by the wind and just bogs down any heavy vehicle.
