I have never been to Desert Sun resort myself, but according to their website, they are clothing optional, except on the pool deck itself. Please check out Desert Sun's website, where it says "We are clothes free in the pools, jacuzzis and on the pool decks. You are free to be nude or wear what is comfortable anywhere else on the resort grounds. There is still plenty of grass around the pool if you feel more comfortable in a sarong. It is the best of both worlds."

So, according to their website, if you don't care to sunbathe nude, you can sit on the grass without any problem, just you're not supposed to have clothing on the pool deck. I think that most likely after you've been there for a couple of days, you will be fine sunbathing nude, but it is up to you. Personally, I find most nudists to be extremely accepting of others, regardless of their state of dress or undress. I don't find a reason myself to worry about what others wear or don't wear.