floor pans

It is a new unit. Would polarity be an issue. I tend to feel it is just a new experience for me. Just someone show me and make sure the machine is set up properly and I should be good to go. Thanks for the advise.
I'm going to have to go use Dad's flux core machine just so I can give decent advice. Been running MIG too long to be a lot of help. Polarity is usually changed for aluminum and sometimes stainless.