Are you eating it or smoking/vaporizing it? I think it depends on ROA because when you eat cannabis some of it gets filtered out in the liver.
I think 10mg of THC(not cannabis/flower/wax/weed) is the "standard" serving/dose. If you're eating it then I'd start somewhere around there and wait 2 hours at least before redosing.
If you are smoking/vaporizing, I would say stay away from concentrates like wax/dab/rosin/etc, and try just a small puff of flower. Wait 30 minutes or longer before redosing.
With no tolerance a hit or two will get me pretty stoned for 3-4 hours if not longer. A dab is too much with no tolerance, but maybe a little dab would be fine. Just go slow, you can always take a little more but you can't take a little less,
