The important thing in Electrical/Electronic troubleshooting is that you UNDERSTAND the circuit. Using the meter is the easy part. I would suggest that you find a good book on the basics or take a JC course on basic electricity. Once you learn Ohms Law you will know the alphabet so that you can figure out the rest of it.

That said, when checking for voltage, ground the black lead and use the red lead in the DC Volts mode to probe for voltage wherever the procedure is telling you.

To check for resistance, go to the Ohms mode and connect the leads together to make sure that you have near zero Ohms, then start testing the component.

LOTS of this will be determined by your particular meter.

You might be best served just buying a test light and using that. There are MANY techs who don't even own a multimeter but do all sorts of troubleshooting with a test light.

Good luck,