Your trichs. Take a trim leaf and look at it through your scope. You should see a sticky looking "oil" that should be pretty clear. As they mature you will notice that the trichs change from clear to cloudy and finally amber. The trichs at first will look as if there is a ball on the tip, this will breakdown as it matures, meaning trichs aer degrading faster than they are being produced. Most aim for about 80% amber, but that is pretty subjective. Some strains the trichs do not turn amber so I look at a combination of maturing signs. ie..... Calyxs swallowing hairs, hairs turning amber, leaves turning a fallish looking color, denseness of the buds. To name a few.