Make sure you are not pushing down too hard on the machine head, causing it to stop rotating and just oscillate. That will cease to Polish at that point. An easy way to keep yourself honest in this regard is to put a verticals line with a permanent marker on the backside of the backing pad. Then watch that mark as you polish, making sure it is always spinning around. If it ever stops spinning and ans just starts oscillating back and forth in one spot, you’re pushing down too hard.
Make sure to clean the pad frequently and/or change it after every body panel.
Start off at 5 or 4 and stay there for the cutting or polishing. Save the lower speeds for wax application or removal.
Less is more when it comes to product application on the pad, especially after the initial application to a fresh pad.
Stick to one body panel until you have it looking like you want the rest of the car. Once that is done, apply whatever techniques you used there to the rest. (You may find this particular paint requires more passes or lower speeds, etc. No use in doing the whole car only to discover you’ll have to do it all again.)
Those are some of the tips I would offer to help make the job easier and increase the likelihood of success.