a) sit on top of the toilet lid. (convex shape isn’t too comfortable, there’s a danger of sliding off and no one’s totally convinced by their ability to take their weight)
b) sit on the seat, but with your trousers up. (probably the most hygienic option, but it feels really weird to sit on a toilet fully clothed, and there’s always the nagging worry that some form of ‘muscle memory’ will kick in when you’re drowsy and you’ll shit your pants)
c) sit on the seat, but with your trousers down. (allows for easy discharge, but will add time due to the inevitable need to wipe etc.)
d) curl up in a ball on the floor. (utterly, utterly mental, and probably necessitates puddle-dodging)

Also, where do you put your head? Rest it on your arms? Balance it on the puppy-soft roll of loo paper? Lean against the wall?

Any other techniques or tactics?

I just had a 30-minute power-nap, btw. I can now keep going for a couple of hours.