Cowboy's Beach Greeting

Alright, listen up, you're not the sharpest tool in the shed, are ya? Here's the breakdown: this is a wordplay joke based on the sound of "sandy cheeks." It sounds like a name, but it's also what your butt would be like after sitting in sand for a while. So, the cowboy is saying "Sandy cheeks" like he's talking to someone, but it's also a description of a sandy butt. Get it? It's supposed to be funny, even if you're too slow to catch on.