I waxed my car the other day, and I noticed some light swirl marks when the car was in the sun. I waxed by hand, using a light coat and avoided using circles when applying. I've waxed it before with no problem, what gives?

 

Swirl marks are inevitable. You can put a lot of effort into minimizing them but eventually they'll rear their ugly head. Every time you touch your paint whether you're washing, drying, QD'ing, or waxing you're causing some level of friction and abrasion. Abrasion eventually leads to swirl marks.

You can remove the marks using a polisher or you can choose to fill them using a glaze like Meguiar's #7 Show Car Glaze. Filling is very temporary and usually the effect lasts maybe a couple of weeks if that.

 

Awesome detailing guide!

 

Thanks!