Sometimes you need a scope to see the resin glands (trichs) and when they are amber that means couch lock and ripe as can be. Next step would be degrading thc.
Trichs start off clear then move on to change colors, amber being last. If you have a leaves that are thin and long you have a sativa plant you want clear/cloudy trichs (10-12 weeks) if you have fat small leafs its a indica and amber is best 8-9 weeks.