Well here goes my answers to you two
Chrissy,
well if you run from an A note up to the next one you have to play 12 different notes. If you remember the piano keyboard there will be 7 white ones and 5 blacks.
Letters represent the seven whites (A to G) so there has to be a notation to represent the black ones. That's where you use the sharp and flat thing. So for example, starting from a D note, if you want to go to the black right above it and not drectly to te next white (which will be E) you have to write D# ... or Eb. That's fine with the piano and only the piano!
Just let me know in case you want the full explanation
-------------------------------------------------------------------------
Droops,
well as i told you previously i don't use to play the guitare so i don't really know how you proceed to build yourself a bass line... Of course playing the piano we have chords you may not be able to do.
But here is an (jazz) exmple of how you could proceed, you probably know it already:
On a II-V-I progression, you notice that every 7th resolves down a half step into the third of the next chord. So play the 7th of each chord and go down a half step to the third of the next one. this will provide you an instant background for the soloist playing with you
and well une muse is ... a muse
PS well I assumed you know what a II-V-I progression is. But if nobody teached you that you won't, so don't hesitate to tell in case you would not know.