Now it is time to put what we have learned into action. The band wants to play a song and they hand you the sheets. Is it time to panic? No, it is time to look ahead and put your knowledge to work.
First, look at the key signature. If they hand you a lead sheet you should (from the lessons above) be able to tell what key you are going to be playing in.Sometimes you will just be handed a chord sheet with the ke on it (if you are lucky). If not ASK somebody. Last but not least ... determine the key from the chord structure. You should be able to do this from the lessons above.
Identify and circle chords that do not fall naturally into the key structure. For example: your playing in C and you see the following chords: dm, G7, em, am. You know from previous lessons that these are all chords of the C scale so you dont panic yet ... then ... BflatMaj7 appears. No problem though. You circle that chord so you dont forget it's coming and when it comes up you will be ready for it.
Note the changes that the new chord brings. Why struggle to find a new scale when you can just remember the changes. Our BflatM7 only means for that measure (or for as long as that chord is there) we just have to remember that the B and E are flat. Now we have several choices. We can: remember to change any B or E to Bflat or Eflat and play in the same position; move to a Bflat scale position if the chord is going to be there a while; avoid B and E entirely; or just dont play over that chord. NO PROBLEM.
Look for key changes and mark them remembering the new changes. If while you are going through the sheets you notice that the key changes or the chords tell you that you have changed keys then mark that section so you know when you come up on it. Also note the changes to the current scale (you may even write them down somewhere.) More then likely you will move your hand position to a position with the new scale in it. This makes it easier to compose on the fly so you are less likely to hit a wrong (unintentional) note.
Don't Forget to check the new key change for chords that do not fit in that key structure. Mark these as well ... note the changes and write them down or avoid them entirely.
If you are just going to be playing the chords then you will have to note any major changes in hand positions and key changes. Mark down any trouble areas and decide what you will do ahead of time. If you are still on the 64 chord system remember to reduce all altered chords to their Maj7, Dom7, and min7. So if you come up with an A7flat-9,flat11,13 dont panic just play A7 and be happy.
Making mistakes is cool, letting people know is not cool. If you make a mistake don't alert everyone in the room about it by yelling S*** or D***. And don't treat the audience to the silence of failure (in other words, don't just stop playing). If you hit a wrong note then hit it again ... and again and ... (don't over do it though). Remember, its not always the note that you're playing at the moment that shows a mistake but often the next one. Make that one right.
If you make a mistake on a chord then repeting it is not always a good idea. Try sliding (an I do mean sliding) your hand down one fret ... you may get lucky. If not slide it again. If you have to slide again they will know you are in trouble but if you keep going and end up on the right chord they will think you are a genious.
Finally, if in doubt STOP or at the very least play quietly so any mistakes you maky will be lost in the wash (hopefully). The audience may notice your absence but will apreciate your judgment. And remember to have fun ... it's just music after all.