How can i test a turn signal switch for turn

I turn the marker lights on (headlights on half way)   then turn on the right blinker and walk around the vehicle then the left   then the four ways.   If you mean when you removed the switch then i would use a multimeter and test for closed circuit.    Remember there are relays that do the actual work and if there is a problem you usually have to replace or at least knock the relays to release one if it was fused into a closed position.  I usually replace the thermal flashers with 2 electronic flashers (another possible place to troubleshoot)