1st, dont get to harvest out of breeder timetables, you harvest with mostly milky trichomes if u want it to be a head high, and mostly amber trichomes if u want a more sedative high, the later will also improve the yield.
2nd, don't overdo it on nutrients, auto's need less than photos and will do fine with using half the dosage as the max ever given dosage.
3rd, train your auto's prior to entering flower, auto's recover from well performed training pretty quick, so if you do it well she will recover in 1 to 2 days.
4th, water more often or with a bigger water volume, this will suposedly make the plant not turn cristals amber so quickly wich allows for better crystal conservation while she is still growing.(this one is highly debatable)
5th, using a pk booster from the 3rd week of flower onwards will help your nugs fatten up more, even if they get slight damage to the leafs they will grow in size more, just remember 2nd point when you do it.