Using your DeWalt DWP849 Variable Speed Polisher is easy. First, make sure you've attached the 2 - position side handle for better control. Connect the backing pad according to your needs. Before starting, set the maximum speed on the variable speed dial based on the material you're working on. For softer materials, a lower speed might be better, while harder materials can handle a higher speed. Once you've set the max speed, use the variable speed trigger to control the actual speed as you polish. When it comes to maintenance, keep an eye on the external brush caps. If they show signs of wear, it's time to service them. Also, use the large spindle lock button to change the backing plate when necessary. Always unplug the polisher before performing any maintenance tasks. Store it in a dry place to prevent rust and damage. With proper use and care, your polisher will serve you well for a long time.