ok, i use steel wool on the real tricky bits if it has alot of detail where s/paper can't get at, a scraper 60, 120 240 s/paper for your mouse sander and a larger sander for the main pieces and some white spirits to clean in btween sanding. And lots of rags
it would be better if you had the machines but elbow grease and a sanding block works just as good
once you have gone thru and sanded down thru the grades of paper to get it really smooth and haved cleaned it with spirits and a rag not water you can apply your first coat of what ever you choose to use
for me i would choose a light satin matte but it depends on personal taste.
put it on with a brush [plus tape around any panels that you might have, masking tape and news paper] and do one piece at a time, so the long bit 1st on one side then grab a rag and gently rub it in taking off any residue then the next long bit another rag yada yada yada.
brush with the grain and don't paint into the next pieces ie; colour in the lines if ya get me...
depending on how dark you want it give it 2 or 3 coats read the can to see how long to leave in b tween coats usually touch dry will get you away with it if you're in a hurry.
If you want to varnish it, again personal taste 2 light coats are better than 1 heavy and when the first coat is dry you can hang your door or hang it when you're fully done but use say a 320 grade sand paper going with the grain LIGHTLY sand the 1st coat of varnish [or you could have just left it with the matte finish] and then give it another light coat[ water it down a bit with spirits ] and that should keep you out of trouble
thats a good freebie for ya