Doing soil or Coco?
If you said I dont remember…
If you have an accurate scale you weigh the doses.
I just use 1/2 tsp part A and once its dissolved then 1/2 tsp part B.
No problems. Weighing is more accurate, but Jacks is pretty forgiving.
Once flowering starts I use a rounded tsp of A to kick up the P&K levels.
I will link a couple threads for you to research.
And yes, Mix up and then adjust pH as needed.
I grow in coco and once mixed in RO water it lands on 5.8 with no adjustment needed.