Although the net is full with info about how to do it, on YouTube is also full with video tutorials, so you can ask what the hell is this guy writing for .... well, here are my 2 cents without a video.
I would have done a video but in a one room appartment is quite hard to do all, so I focused on the results.

Picking the stains
There are two types of wood stains - water based and oil based. My favorite is the water based stain, because when it dries you have no pain on what goes over the oil or what you can use.
Powder or ready made - I prefer the powder ones so I can make it a bit stronger than the ready mixed, but anyway you will dilute them anyways for achieving different shadings.

Applying the stain
I sand the wood up to a 400 grit, clean all the dust and check for any glue stains or whatever will block the stain from being absorbed.
I usually apply it with a cloth rather than any other tools - gives more control over the application, and you can shade it neat and in a short time, also offers shorter drying times. A brush tends to let more water on the wood than a cloth, it also has a longer waiting time to dry between applications.
Between "coats" give it a dry time of 4 - 8 hours - by a coat I mean the stage where I am happy with the result and the next step will be a different shade or color.

I usually do sandings between applications with a 400 grit paper only if I need to modify the shade of some color / area, or the wood surface has become too coarse due to the water stain.
Final sanding is a light sanding with a 340 or 400 grit paper, to smooth the wood and prepare the surface for the final sealing / finnishing.


Sealing / Finish comes for me in two flavours:

Chemical stinky coating

I use a nitro based sanding sealer in two light coats to protect the stained wood and light sanding with a 340 grit between coats and after the second coat of sealer.

Although many love a nitro finish, I like the poly water based finish, in two coats can be achieved a good gloss.


Hip natural coating

Oil based sealers from the "hard" oils family, they do seal well due to different waxes contained in the mixture and they do get quite hard after they are dry.

If enough oil coats are used there is actually only a small step to the final product: polishing.
After the base hard oil is cured I usually use one of the following:
- gun stock oil - takes many coats but it polishes nice, and if you apply once a year a new coat, the wood remains like new for many many years.
- shellac - the problem with the shellac is that is not color neutral so it has to work 


In the following weeks I will continue with images of the guitars I painted and what I used.