Calcium:

Mix 3 tsp CaCl2 with 1 cup water. Dose 1 tsp of this solution per gallon.

Magnesium:

1 tsp MgSO4 with 2 cups water, dose 1 tsp of this solution per gallon.

Potassium:

Dose 1/8 tsp of KCl per 10 gallons of water.

Bicarbonate:

Dose 1 tsp baking soda per 10 gallons water.

Please double check the calculations, but I hope this makes it a bit simpler I think I still did some tweaking at each level to get the exact hardness I wanted. Went through quite a few vials of tests that night!