Porting and Polishing is a step by step process. There are many steps to Porting and Polishing, six to be exact. There are many tools that will be needed in this process too. Porting and Polishing is just basically when you just smooth out the ports where the air flows through the head into the cylinder without restriction. You will get two effects out of this. You will have more horsepower do to colder and more denser air. You will also get better gas mileage. This research paper will discuss how to port and polish a head.
First step would be rounding everything up. You will need the head or heads if you have a v type or boxer engine. You will need to take all of the guts out of the head such as the valves, cam/cams if its an over head cam, and put them in a hot tank or soak them in brake parts cleaner and put the head in a hot tank to get all of the corroded up oil and gunk out of it. You will also need your tools such as a dye grinder, sand paper, the tools to tune the engine after the head is back on, the tools to take apart and put the head back together with. A torque wrench will definitely be needed in this process. You will also need someone or if you're going to buy a laptop for tuning, the app you need to download for the tuning process and you will need to ship your ECU chip to get flashed and that basically just makes the engine relearn the power and torque of it. If you do not do this you will have worse gas mileage and just the same power as you did before because the computer/ecu will limit it.
The second step would be to start on the porting and polishing. First off you will need to remove your valves, cam and all other components. After everything is removed you will need to port the intake and exhaust ports as if the head was on the engine. You will then need to start on the top of the head in the intake ports. The intake ports are the only ports on the top of the head so it should be pretty simple. You will then need to blow all of the shaved off metal with an air hose. Now to the polishing part, you will need to take the 80 grit sandpaper like bits and start polishing. It doesnt matter how you do them you just have to make sure that they are done equally. it will look pretty rough at first but thats just because you're using the 80 grit when you get up in the 200’s it will look nice and pretty. you just move up with the sandpaper grits and you just keep repeating.