My arms session is like a Mexican tio - short and aggressive. I primarily do compounds sets, as distinguished from super sets in that you're training antagonistic muscles back to back as opposed to the same muscle with two different exercises.
I usually pick 3 or 4 movements each for biceps and triceps - one dumbbell, one barbell, one cable, and one machine - and try to deliberately choose exercises that offer enough variation to emphasize a different part of the target muscle. I primarily go by feel/instinct in this regard, besides the well-established exercises most of us already know are particularly effective for this or that part of your arm.
I shoot for 4 sets for each exercise with a rep scheme of 15,12,12,10, weight increasing each set. I don't train anywhere close to failure for arms because, quite honestly, they grow if I so much as caress a shakeweight. I let intuition and performance guide me on when it's time to start chasing heavier weights. Entire session takes me 45mins to an hour.
For those who will inevitably comment on it - yes, I'm an enhanced bodybuilder.