Yeah, I always recommend that a polish be used before waxing/sealing. Use the clay first, and then use a polish. Be aware that there are many different levels of polish, and if you're going to be using it by hand, do NOT use an aggressive polish. You'll likely be biting off more than you can chew, as they say. Though aggressive polishes are only needed for serious swirl/oxidation correction, so you may not need that in the first place. A light polish will just clean off oxidation and maybe remove/hide some very minor swirls.
If you don't have any already, get some high quality microfiber towels, and learn to wash the car properly (it's more complex than most people think). These two things are the most common causes of swirls on vehicles.