I'm relaxing at a camp site after the 3rd week of teaching another frame building class. My student had literally no idea whatsoever how a frame was put together and English is his 2nd language. Fortunately his frame turned out beautifully. Determination can make up a lot for any lack of skills. And years of teaching experience helps. He'll stick around and we will paint it together next week. So answering this question is a little like getting called to go back in to the office for a couple of hours after you've left for the week. Because of that I'm not going to review all your steps but just provide some basic suggestions.

Let your primer set up as long as possible. Auto respray places want to move as quickly as possible through the whole process to make a profit so they are focused on as little as possiible time delays. I assume you can take your time. I usually put on 2 or 3 primer coats. I wet sand the primers with 600 grit paper. Then I apply the color casts. The House of Kolor paint I use requires putting clears over color coats without delay or that can weaken the bond between coats. The time between the color and clear depends on your paint choice. Now again I would let the clear have plenty of time to harden (I'm assuming you have activated clear that hardens by chemical action). These are your intermediate clears designed to protect your fragile color coats. You can speed up and improve this process by putting the frame in a car parked in the sun. Use courser sandpaper like 600 grit on your intermediate clears (at least 2 coats to prevent sand throughs) so the later final clear coats can bond better with the hardened clears. Now you can do whatever with decals without worries about time windows before putting on the final clears.

Polishing final clears is a whole other chapter.