B -- swinging punch. Also enables Banjo and Kazooie to swim underwater when they are floating above.
A -- Jump. Also used for special functions, such fly-pods and jump-pods.
C-Up -- Zoom camera in. Also enables a first-person, look-around view.
C-Left, C-Right -- Changes angles.
C-Down -- Zoom out.
Z-Trigger -- Duck
Z-Trigger + A -- Banjo flips into the air and Kazooie spreads his wings. Very similar to Mario's back-flip.
Z-Trigger + B -- Banjo dives forward with Kazooie's beak extended
Pressing B in the middle of a jump will also extend Kazooie's beak for an attack.
Press Z-Trigger in the middle of a jump and Kazooie will point his beak downwards for a beak-stomp (exactly like Mario's butt-stomp).
Run + B -- Roll attack.
Holding Z-Trigger and then pressing C-Down lets players use Kazooie for navigational purposes. Kazooie is much faster and can run up steep hills.
Jump on a tree, pole, pipe, or somting else like that to climb it.