Clear trichomes- not ripe. Doesnt mean it isnt smokable, but it wont be in its prime overall. It will lack potency and possibly may not have hit its peak terp profile either.
Clear/Milky trichomes- Still not fully ripe but getting close so pay attention. The window between now and ripeness is getting smaller. The milky thrichomes are an indication that the buzz will almost surely be more intense and last longer than if harvested when all clear.
Milky trichomes- Your flavor and terp profiles are likely going to be on full tilt at this point. Terp hunters may find this a perfect time to chop as to preserve the harvest at its highest peak of flavors/aromas/etc but possibly at a sacrifice on potency.
Milky/Amber trichomes- It is fully ripe & ready for chop, as this is considered by most to be the "peak" time to harvest. All cloudy means it is peak flavor/aroma etc, while the amber almost guarantees the full effect that the plant is capable of. Amber in the mix is the plant saying that it is ripe and you have seen pretty much everything it is capable of. The potentcy at this point will be at about peak as well.
Amber trichomes- If you are about full amber than the plant is past its "ripe" stage and in terms of fruit, it is getting bad and the levels of thc and all of the flavor profiles are decreasing as the days pass.
Obviously this is all very subjective, but it has been a good gauge for me over the years.