im am just learning, but one thing i have learned so far is you have to do what works best for you, yes there are rules, i can count very quickley so to get my chords i count in half steps this is what works for me.
MAJOR --------------------------------- R-4-3
MINOR-----------------------------------R-3-4
AUGMENTED-----------------------------R-4-4
DIMINISHED-----------------------------R-3-3
MAJOR 7----------------------------------R-4-3-4
SEVENTH----------------------------------R-4-3-3
MINOR SEVENTH-------------------------R-3-4-3
SIXTH-------------------------------------R-4-3-2
MINOR SIXTH-----------------------------R-3-4-2
DIMINISHED SEVENTH-------------------R-3-3-3
R---BEING THE ROOT OF THE CHORD I STILL COME UP WITH THE SAME CHORDS FOR EACH, THAT IS BY COUNTING IN HALF STEPS . AND NOT THE WHOLE STEP WHOLE STEP HALF STEP FORMULA.
IF I AM WRONG AND OVER LOOKING SOMETHING COULD SOMEONE LET ME KNOW