That being said, how does one become a good jammer? I will give my ideas and tips in this instructable, feel free to comment any additional ideas.
In my opinion, jamming is the art of faking, so it does not take a seasoned musician to jam (fake) well, a novice can do it. Don't be afraid to jam because you have only been playing guitar for 2 months or because you dont play an instrument. Anyone with any instrument can learn to jam, I will gear this instructable however to the guitarist.
Remember, everyone can play the washboard. ;)
Step 1: The Truth About Jamming
It is good because that means in most jam sessions you will only need 3 to 4 chords. This appeals to both beginning musicians and more experienced musicians because the beginning musicians can comfortably rock out with the chords they know and the more advanced ones can focus on the fun stuff like chord transitions, solos, and making good sounds (i.e. feedback)
If you get bored with playing the same three chords over and over again, add something new, be creative. DONT, however, forget that you are a team player and not a diva. I will cover this more thoroughly later.
If you are an artsy musician who likes time signature changes, modulations, and funky rhythms every other measure, jamming is not for you. Get some sheet music and join an advanced jazz ensemble.
Step 2: Get Yourself to a Jam Session
Starting a jam session can be tricky if you don't know a lot of musicians but give it a whirl if you want.
Step 3: What to Jam To
When you are jamming it is ALL ABOUT THE BLUES. blues blues blues blues. If you don't know the blues: EAEBAEB, there you know the 12 bar blues.
My point is that the blues chord progression of:
I IV I V IV I V (repeat n times)
is easy to pick up, but can be very technical, melodic, whatever you make it.
If you want examples of melodic, technical, fast, soft blues listen to:
Stevie Ray Vaughan (technical, fast)
B.B. King (melodic, slow)
Jimi Hendrix (melodic, technical)
Eric Clapton (a little bit of everything)
They are widely regarded as great bluesters. Although there have been MANY others (see John Lee Hooker above)
Very few people can play a Hendrix blues note for note, that is not the idea. Just listen to it for ideas what a blues master does.
Step 4: Expanding on the Blues Progression
Even if you are only playing the root chords ( E A E B A E B ), you can still vary things up between repeats. Make one go real soft and the next one loud, for starters.
Up to this point I am assuming that you are playing blues in E, the most common blues jam key. You are not limited to this though! Give A a try! ( A D A E D A E )
Step 5: NOT Being a Diva
-- dont try and do a tapping guitar solo , it is annoying, selfish, and annoying and chances are your not doing it right (I'm not bagging on fledgling tappers, keep it up, but leave it outside when you jam.)
-- keep the tempo ! It is better to stop playing and regain your place than losing the tempo. Also be on your guard against speeding up esp. on the guitar.
-- if you're playing with beginners, dont outdo them too badly. Its rude.
I feel i should explain the image. The woman in it was an opera teacher while I was in high school. I stood in the back row struggling to sing tenor 2 while she sang a big ol' aria. Heh.
Step 6: Adding Other Instruments
I should say, however, that beginning piano players and beginning guitar players don't mix. Pianists all want to jam in C and Guitarists prefer A or E.
Step 7: Other Material to Jam To
Riders on the Storm -- The Doors (plus violin equals awesome)
La Grange -- ZZ Top
Smoke on the Water -- Deep Purple
Purple Haze, Hey Joe, Wild Thing -- Jimi Hendrix Experience
Wipeout -- The Ventures
Highway to Hell, You Shook Me All Night Long -- AC/DC
Money, Comfortably Numb -- Pink Floyd (Comfortably Numb is a bit tricky)
Just What I needed -- The Cars
Hotel California -- Eagles
Stay away from Metal unless it is simpler (Black Sabbath, Anvil) because metal can get really insane really fast. You really have to know what you are doing to pull off an Iron Maiden or Pantera Song. Earlier I defined jamming as "artful faking." There ain't no way to fake your way through "Run to the Hills"
The Idea with Jamming is not playing a whole song, that is more the performing side of things. So dont feel obligated to play a bridge or even the complicated half of a chorus. Just find something that works and develop it into something of your own.