The Technika has become my preferred Hawai'i camera, so it's often in sandy environments. I've posted a couple of examples in the past--
As long as there isn't sand in the rangefinder mechanism, I wouldn't expect it to be that difficult to clean, actually. Most of the mechanical parts of a Technika are exposed and easy to access and should be dry, so there isn't any lubricant for sand to cling to, at least in the exposed parts with the exception of the focusing rails. I'd just take apart what can be taken apart without a screwdriver--the groundglass cover, the groundglass panel, the back, the accessory shoe, the lensboard, the rangefinder cam, and the focusing rails--make sure everything is dry, and vacuum and brush it all out, and use canned air in places where the air won't force sand into places like the rangefinder mechanism or the Graflok slides. Some parts like the focusing rails can even be rinsed under water (when removed), dried, and relubricated with Vaseline (I've read that this is Linhof's recommendation, but I use lithium grease).