If you want cautionary example to inform your undertaking, here’s my advice. My first run baking I used 6” and 9” pans; however, I failed to notice that the 6” pans were 2” high and the 9” pans were 1.5” high. Thus—and because I did not have a scale to weigh the cake batter precisely—I eyeballed the batter quantity and ended up with two very high 6” layers and two very short 9” layers.
I would say that the magic strips are an absolute must. I did the heavy duty foil and wet paper towel trick and found it worked perfectly but was a little time-consuming. I think I will plan on just getting the strips next time.
Sadly, shortly after I did the baking, everyone in the household got hit with the flu, and I ended up having to order my daughter’s birthday cake while I ran the sick ward. The bakery cake was delicious, but I was so disappointed that I didn’t get to bake her cake myself!