? about how to paint my camaro

[almcbri]

I am trying to get this straight before I attempt to paint my car. I see various ways that guys paint these camaros and I want to do it the correct way the first time.

I have always thought that I would base/clear each panel off of the car and then re-assemble the car. In this picture, these guys are jambing the car with base and clear. Is there some special kind of clear that they are using? In my mind I am thinking there would be a ridge between the exterior body panels and the jambs from where they are taping off.

I see these dudes know what they are doing and I am not second guessing what they are doing I just want a clear understanding of what is going on.

Another question. I notice this guy is using a sharpe marker. Anyone else do this for a guide? Pretty good idea I thought. If any painters can chime in and let me know a good route I would appreciate it.