It's real easy bro. Figure out what dosages of each you want to run.
For example, you want 150mg of compound 'A', but it's 250mg/ml. Just divide 150/250 which gives you 0.6. That would be 0.6ml for that compound at that concentration.
Do this again for each one and you'll know how much you need to pull from each vial.
After awhile you'll just memorize them. Hope that helps.
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