While Plasma Arc Cutting is one of the easiest methods for metal cutting and is a good choice for beginners, there are several mistakes that people make that result in an inefficient process. By following the steps from http://plasmacutterpro.com/, it will help you optimise your performance and produce much better quality results as well.
Hold the cutter correctly
The most important part of the entire process is ensuring that you are holding the cutter correctly, since a mistake with this can completely ruin your project. A good way to ensure stability is by supporting your cutting hand with the other hand to steady it.
Another way to improve performance is by pulling the torch towards you during the process rather than pushing it away.
Maintain the right distance
In most cases, the torch needs to be held at a distance of 1/8th of an inch away from the metal. It might vary slightly depending on the requirements, but ensure that you maintain a constant distance throughout the process for a good, even cut.
Trace the intended path
Without actually starting the cutter, make a couple of practice runs along the path you intend to follow. Longer cuts are tougher to make, so be sure that you can maintain a steady hand for the entire duration. Also, be sure that you can make the entire cut without needing to change your position, since this could cause errors in the cut.
Work with a sample first
Before starting the cutting process, test out the torch on a sample piece of the same material as the work piece. This allows you to verify that the amperage is correct and also gives an idea of the speed and time required to make a good cut.
If sparks are shooting out of the top of the material, you are moving the cutter too fast. Ideally, the sparks should exit only at the bottom surface, and at a slight angle opposite to the direction of travel of the torch.
If you are cutting a work piece that is close to the maximum thickness possible for your cutter, then dross might be formed. Dross is basically molten metal that has not been blown away by the compressed air flow and instead sticks to the bottom of your work piece. It can be removed later on by using a chipping hammer, but a better solution might be to get a more powerful torch.
Adjusting according to thickness
For thinner work pieces, it might be faster to simply place the torch on the surface of the metal and pull the trigger, since the force of the arc can easily punch through the metal. However this should only be attempted on very thin work pieces since thicker pieces could produce a blowback of molten metal that damages the head of the torch.
For thicker work pieces, be careful when cutting through the last piece of metal, since it generally requires you to spend a little extra time on it to ensure a clean cut.