Pff that sucks !!
You don't have any idea about your position in the map. but no worry the easiest way is to send him an SMS with WineK Application to give him your position in 2 seconds
it's really a simple application you have just to flow 4 steps
-Enter to the app
-Click to the SEND MY LOCATION button
-Click on the person
-Confirm the sent
even if your friend doesn't have the application he want to receive a message with your location and with maps he can flow you