Phew! Where to begin? The best advise I can give you is read up and learn as much as you can first before doing anything. Visit
Guitar Reranch, who have most of what you need to know about the techniques and tools. Read everything repeatedly. Then read it again. ? Consider getting a book or two from Stewmac too.
A big gun is actually good enough to do everything - an airbrush is more for fine detail or artwork and is
much more difficult to use in larger areas where you want to get an even colour - especially for a beginner at this. HLVP (high volume low pressure) is ideally the way to go as you waste less finish and don't end up with 3/4 of the solvents in the air.
Candy finishes are not translucent, they are solid opaque finishes. They are also tricky to do, so not the best choice for your first ever finish. It's a multi-layer approach and if you screw up anywhere in the proceedure it's strip down to wood and start completely from scratch.
Here's a guy who documents a candy orange finish.
Chances are that even though your mahogany body is a decent piece of wood, it won't be the best looking piece for any kind of transparent finish - manufacturers are pretty good at saving the best looking pieces for their transparent models. It may be quite good, but don't expect any laminates to match each other perfectly.
You don't need to mask for any kind of burst BTW, it's done freehand.
Stripping poly finishes is a difficult job and even worse on a curved top. The best technique is to use a heat gun to soften it and then scrape it off. Just be careful not to overheat any area as you can make any glue joints soften and then the body falls apart. Otherwise, I usually chip off the old finish slowly and carefully - which is also tricky to do without gouging a carved top. Sanding would likely take you weeks of work by hand.
Once the finish is removed, sanding. Use a rubber block. For a carved top , the smaller the better. It's slower, but more accurate in the long run. Final sanding with each grit should be by hand with no block - just your fingers. Use wet or dry papers, 3M or similar.
I must get some work done, but if you have any questions, ask (preferably one or two at a time ?).