Yes, you can do so. There are varied techniques used to make the dream world come into focus more clearly--spinning is one, though I don't use it myself. What I do is just focus on detail; focusing on something will often bring it into greater clarity, prolonging the dream. I've often had the feeling of "running out of time", though, or sensed my real-life body lying in bed; so of course it's impossible to delay waking up indefinitely. Perhaps WILD-induced dreams, coming as they do at the beginning of a sleep period, are more easily prolonged?