Ceramic coating on new car and already coated car

Hi I have a 2 part question.

On one car I already had done a ceramic coating approximately 3 years ago using blackfire coating. The car still beads a lot when washing. Car is always in garage when not driven and is a weekend car. for summer months only. Nevertheless I want to refresh the coating by adding another layer. Might have enough of the black fire or else I will buy another brand.
My question is since I want to preserve what is there and add layer what would be the necessary steps?
Usually I know we need to wash, clay, compound, polish and coat. but I am guessing I should skip most of these?

2nd question I am getting a new black car in March. Since it is brand new and planning to do the ceramic coating as soon as I get the car. What would be the steps here? Being brand new besides washing guess I can skip most steps here also?

Thanks

No matter what was done to the car , I would still wash/polish/wipe prep/coat….

If you’re happy with the car that was coated years ago you could just wash it and follow up with the topper of your choice.

You could technically add another layer but have you used anything on top of the coating (ie: spray sealant, wash & coat)?

For a new car the process is the same. You will have to determine what type of paint correction you have to do whether it’s a one step polish or compound and polish.