Slevin,
In the absence of specific local procedures proceed as follows:-
Overfly the airfield at 2000ft AGL and:-
a) Observe the signal square if available.
b) Observe other aircraft in the circuit.
c) Look at the windsock.
Based on the above determine the runway in use and circuit direction, position your aircraft on the deadside, descend to circuit height and then fly a normal circuit.
Also keep a particularly vigilant lookout since being non-radio you may well be a total surprise to all of the othercircuit aircraft.
I would not bother to look for light signals since anytime spent trying to see them distracts you from flying the aircraft safely given that you are, potentially, a total surprise to other aircraft.