If this is because you want to feel cooler, place the fan so it blows cool air inwards onto you. You'll get far more benefit from having air blown on you than you will from just dropping the ambient temperature around you.
Air conditioning -> cool human by cooling environment
It only accelerates the speed at which your skin temperature moves to match the air temperature through convection.
If you can move air elsewhere to lower the temperature of the room, that is better long term.