Besides this:
The lower 3 drawbars are the power drawbars
the upper 3 are the sizzle
the middle 3 are the spice
Spend some time holding a single note and pulling drawbars one at a time to train your ear to the various pitch relationships.
Drawbars are color coded and assigned numbers relating to pipe organ terminology relating to length of the largest pipe in the group. 8' stops sound at concert pitch, 16' an octave below, 4' an octave above, etc. Later Hammond models had these numbers engraved on the drawbars, earlier ones did not.
White drawbars sound the concert pitch note and its octaves.
Black drawbars sound the fifth and its octaves (except for one which sounds the third.)
Farthest left drawbar is the sub octave. Playing chords with this pulled can get muddy if you are playing them around middle C (which is the 3rd C from the left on a 5 octave organ with the first white drawbar (8') pulled out.) So when playing chord pads you may find it more pleasing to play in the next octave than you would on a piano.
2nd brown drawbar sounds a fifth above the 8' which is not a natural harmonic but is considered the rock and roll drawbar. 2nd black drawbar from the right is the Sporty Spice of drawbars, sounding the 3rd 2 octaves above.