Kha'zix jungle - how do I know whether to kill the small minions first

I don't know but I imagine yes it's good to kill the small ones first because they're weak and you get bonus damage on the big one because it's isolated....

Early clear I think it's kill small first. Then later just whatever.

As a rule, if a jungler does not have good aoe damage or high sustain, clear small monsters first - it decreases the damage you take greatly.

Kill small ones first. They deal a lot of damage without having a lot of health, and by killing them off, you can get the main one Isolated.

Kill the small ones first for buffs, Krugs and Raptors.

Less important for wolves, but still an option.

Here is a good clear guide: https://www.youtube.com/watch?v=16_HrQvjo20

This guy is really good at Kha'zix

Here is a montage of him on the bug:

https://www.youtube.com/watch?v=SRxwngdCS3Y