First thing is learning how to tune the banjo. To know which string is which is easy on the banjo. The shortest string, with the tuning peg on the side of the banjo is your 5th string, it of course is next to the 4th, the 4th next to the 3rd etc. The string farthest away from the 5th string is the 1st string. (same designation as a guitar but not tuned like a guitar). The standard tuning for a 5 string bluegrass banjo is the following.
The 5th string, the short one with the peg up the neck is tuned to G above middle C.
The 4th string , one directly next to the fifth is tuned to D below C.
The 3rd string, one directly next to the fourth is tuned to G below middle C an octave below your 5th string.
The 2nd string, one directly next to the third is tuned to B below middle C.
The 1st string, furthest away from the fifth, is tuned to D above middle C.
This is the standard tuning of a bluegrass banjo. There are differant tunings used upon occasion, however this is the standard. When you strum your banjo, you should hear a perfect G chord, without having to push down or "fret" any strings. Be gentle yet firm while turning your tuning pegs. Try to make a habit of holding the banjo so if a string would happen to pop, which does happen now and then, it doesnt clip your face. Dont be afraid to tighten your strings, but be cautious.

Now if you don't have a piano or a clue to where Middle C is, you need to get a pitch pipe that has a G below middle C on it or a tuning fork(consult your music shop) and match the pitch. You're matching the pitch to your 3rd string, the G string, once you've accomplished that here's how you tune the other strings. Those little bars across the neck of your banjo are called frets, starting from the top of the banjo, count down four frets for your third or G string and push on it, that will give you the pitch for your second or B string. Match the B string to the same pitch as your fretted G string. Then count down 3 frets from the top on your second or B string and match the first string in pitch. After that, count down 5 frets on your first or D string and match the fifth string with that pitch. Now they are all tuned except for the fourth string. This is a little differant but its really easy. To tune the fourth string you have to count down 5 frets on the fourth string push on it and make it match the pitch of the third or G string. ( just opposite of how you matched the others ). This means you will have to release the fret to tune the string up or down, but you should be able to get it correctly in a few tries.
You can use this last method to tune a banjo, even if you dont have a referance note, using this last technique will have a banjo in tuned to " itself". The safest though is to use a tuning referance, you will break alot less strings if it's tuned properly.

Tablature is the easiest way of reading and writing music that there is. If you can count you can read tablature. Tablature is used on many instruments. Basically, there is a line drawn for each string, the five string banjo having five strings can use standard music staff paper.
The bottom line is your 5th string. For those who read standard notation Treble Cleff, same as E.
The second line up from the bottom is your 4th string. For those who read standard notation Treble Cleff, same as G.
The third line from the bottom is your 3rd string. For those who read standard notation Treble Cleff, same as B.
The fourth line from the bottom or second from the top, is your 2nd string from the top. For those who read standard notation Treble Cleff, same as D.
The top line is your top string or 1st string. For those who read standard notation Treble Cleff, same as F.

------------------- 1st string or D
-------------------- 2nd string or B
---------------------3rd string or G
--------------------- 4th string or D
--------------------- 5th string or G

Remember those frets you counted while tuning? Well thats how tab is written. For instance, if I want you to play an A Id place a number 2 on the third line from the bottom your G string.

If you intend to be good at this it requires a great deal of practice. Granted this first lesson has just been very basic instructions, not alot to practice yet. ( that changes on lesson 2). I recommend you practice at least 30 minutes a day, 6 days a week.( everyone needs a sabbath) This is a minimum. More is better. I know myself, it takes me 20 minutes to get my hands limbered up. Most of the pickers I know warm up for at least 15 minutes before going on stage. So 30 minutes is not really a large amount of time. You are learning new skills, in time with practice you will master them. Or in time you will shut up your banjo case and stick it in a closet. You wont be likely to shove the banjo in the closet unless you arent practicing and growing in skills. Don't expect you can master this in a few weeks. Some people think since they can pick up dance steps in minutes how much harder can it be to play the music. Well, I can play 5 instruments very well, but cant dance a lick. Everyone has differant abilities. The old adage "Practice Makes Perfect" has alot of truth in it. I have taught about 26 people how to play the 5 string. The ones that actually practiced, did very well. The ones that didnt, well thier banjos are in the closet Im sure.