I'm in the same situation as you are. I suggest you do what I've done - go to You Tube and enter "Carenado" "FSX "Repaint". You don't need to enter the parentheses. At least two tutorials will be displayed that I've used successfully.
In fact, those tutorials suggested I review what's in "SimmersPaint shop.com" which is why I'm here now.
There is also information on the Carenado Knowledge Base Website and in the "Unofficial Carenado Support" webpage on AVSIM online.
Suggestion - I open a new document in Word or whichever word processor you use. Save it as "Repaint Info" or whatever you want to name it. Copy and paste the URL website addresses to the document as you cruise through these different websites. Or, you can bookmark each one. The idea is to keep track by title what you have found in an order that organizes and makes sense of the myriad of information you'll see. Otherwise, you'll become confused pretty quickly about what to use and what not to.
Good luck,
Mark Nault