KSM 66 Powder: Serving Size?

I realize the package said to use a mg scale, but alas: I Thought I would be okay approximating. (I regret not getting the capsules unless I can figure out the powder dosing).

What serving size to do you use, those that have this product? Would 1/8 TSP be ~600mg?

Furthermore: I used 1/4 TSP and found it was a bit much (I felt calm, but “altered” - didn’t like that).

Thanks!