>>2097090i've camped on the dunes in may/june more than once and also in sep and had no issue with the sand being too hot. its still pretty high elevation and once the sun goes down it cools off pretty quick.
>>2097085nothing to it other than just regular tent camping, you do not need to dig anything like that guy said and its probably against the park rules anyway. i personally have had the best nights sleep I've ever had outdoors sleeping on those dunes.
they have rules about how far you have to hike in as a minimum to not have campsites in the day use areas. i recommend planning a trip there that includes a night at one of the backcountry sites on the north/northeast side so you are allowed to leave a car there; from that side you don't have to hike into the dunes nearly as far as you have to from the day use area. hiking a pack over dunes is exhausting. pic is from a 2016 trip i think