Hi Sander and everybody
I am a Specialist Steadicam Assistant as well as being a 1st and 2nd AC based in Melbourne Australia.
Alot of being a Steadicam Assistant is simply knowing the gear. Your assistant must know your system and cases really well and know where you keep all the little things that you might need when working. (if the operator asks for his angled d bracket for example you dont want to be asking where is that again?)
Generally I let the Steadicam Operator I am working with build and balance the system (at least on the first day of the shoot) mainly because every one likes their rig set up differently (drop times, monitor placement, etc). If I havent worked with the operator before I will always arrange a time to check out all their cases and formiliarise myself with their gear, just so theres no suprises. Generally on set I end up pulling focus for the Steadicam anyway, but other Steadicam Assistants can end up not doing too much work during the day. Once the rig is set up and the operator has his/her on set bag or case under their stand with extra batts, drink bottle, plus all the usual bits and pieces its pretty smooth sailing.
Like a clapper loader, a Steadicam assistant is very much a luxary for operators here in Australia, plus most of the focus pullers know their way around the system these days any way.
Would love to hear how this differs to what goes on in the US.
James Puli