How do you know what to play in between a key change?? For example:
If you are playing in the key of Eb and you go up to F what do you play in between to fill in?? Any help will be greatly appreciated! 
AS A RULE, YOU FIND THE 5TH SCALE DEGREE YOU'RE GOING TO, IN THE CASE OF GOING FROM Eb TO F, WHICH IS A WHOLE STEP, THE 5TH OF F IS 'C', WHICH IS THE MINOR 6TH OF Eb! SO A KEY CHANGE PROGRESSION CAN GO LIKE THIS:
LH / RH
EbBb / Eb
DbB / Eb
CG / Bb
ED / EGC
FC / F
~~~~~~~~ THAT'S ONE WAY FOR MAJOR
EbBb / Ebm7
DbB / Eb
CBb / EM7(b5)____EbM6(b5)__OR__EAbBbEb____EAbBbDb
FC / Fm7
~~~~~~~~~~ THAT'S A KEY CHANGE FOR THE MINOR
THERE ARE MANY WAYS, BUT REMEMBER TO PLAY THE 5th CHORD OF THE KEY YOU'RE GOING TO :wink: