Hey mate!
You should harvest in base of the tricomes ripeness, to check the tricomes you need to buy a microscope at least 30x.
The tricomes have 3 phases,
First one phase is transparent colour, in this stage the cannabinoids are don’t fully ripen.
The next stage is cloudy/milky colour, in this stage the tricomes are in is best power!
The next stage is amber colour, in this stage the thc degradation forms cbn, Cbn give more a sedative high!
So, I personally like to harvest when the tricomes arr 90% cloudy and 10%amber or transparent! In this stage the cannabinoids are is is full power!
But if you want a more sedative high, wait until more amber tricomes apear, like 60% amber or so!
But the best way is try to cut different plant in different ripeness, and see what you like the most!
Wish it helps mate