personally for me spinning and rubbing your hands don't really work that well for me, but yesterday in my dream i stumbled on a way (it worked for me at least ) to keep a dream long and vivid while also keeping you focused on what was happening in the dream. all i did was every now and then i deliberately (with a bit of force) shifted my eyes all the way to the right and back to the middle, waited 1 second, then shifted my eyes all the way to the left and back to the middle.