its best to undo the tamper proof torx bolts and remove it from the housing. Then i sprayed it cleaner and wiped it with a kimwipe from the lab... but i assume a cotton swab would do.
Personally, I sprayed carb cleaner on a q-tip, and used that to clean it off, but any of the above methods would work just fine. And yes, you definitely want to take the actual sensor out of the housing to clean it.