Hi, what sort of mental tools or theory or anything like it is helpful for developing your ranges in a situation?

If im in a situation, e.g on a river where i want to valuebet a percentage or number of valuehands and then balance this with a percentage or number of bluffs, then how do i sort of count this stuff up? I am aware of what the ratios should be, i just dont know how to count up how many hands to include in the ranges, combocounting doesnt work out in plo right.

E.g on the river ip as pfr the board could be QJ7 4 2 with two tone on the flop and no suit river. Then if i had 2 barreled flop and turn, then i can count QQ, JJ, 77, the other sets being unlikely. Then QJ, i guess Q7 is too weak right. Then i balance this with e.g AKT wrap and AKxx nut missed flushdraw?, (but AKT is a 3 card hand and i assume more rare than e.g QQxx or is the cardremoval of the Q on the board enough to make the holecards QQ count as much as AKT?

You see my point here.

thanks