Finally, there is about a 40 degree area that is safe to polish on. If you polish outside that area its more likely your piece will catch on the wheel and go flying. When you polish ideally your arms will be at 90 degree angle at about your belly button, braced by your hips with your feet planted firmly shoulder width apart.
Preparing a wheel is simple. Just take a hard piece of metal like a flat head screw driver or, like I'm using, the tang on an old file and press it into the wheel. Bits and pieces of material should go flying everywhere. Move it side to side until the fly aways pretty much stop and then you are good to go. This is a good way of also getting excess or old/used compound off your wheels.
On Wheels and Compounds:
Different compounds can take different kinds of wheels. Tripoli can be apply to either a pressed felt wheel (which you can choose either a plain wheel or knife edge), chamois, or muslin. Because tripoli is an early polish and still has alot of cutting power a different wheel will give different results. A pressed felt wheel is the hardest and can be used to clean up edges. I've used the side of a knife edge pressed felt to polish the edges of my back plates and it does wonders crisping up the edges and making the whole piece look thicker! A knife edge will also get into narrow areas, but because it still has cutting power it can leave marks if you don't go fast enough. Felt will cut what it touches and will not necessarily give an even polish to something with raised detail, so that's where your muslin wheels come in. The layers of muslin opens up a bit so they envelope the piece and can reach most detail spots. As you go up in polish grades the wheels need to become softer material so they don't scratch the piece. Sure, tripoli and Zam you can use most any wheel on, but your final polish should be imparted with something soft like muslin.
I have worked with people who are super anal about not contaminating wheels with the wrong compound, and others who literally throw the wheels and compounds all in the same box. Most folks say avoid getting any lower grit compound on your higher grit wheels and clean thoroughly between polishes.
Right now I am only doing two polishes on the wheel. I use red tripoli then go to red rouge. Ideally I would be using Zam between the two for an even brighter polish. Fabuluster is also a great product for silver which i use on my flex shaft and some of my stones. Compound isn't too pricey so you can play around and decide what you like the most.
I'd like to hear what polishes my reader like to use. Anyone use the different tripolis, yellow, white or red? What do you like to finish with? Do you use something different for different metals?