When I started training I used to start feeling ill when I had to look down at my maps, clipboards or at the instruments alone for a prolonged period of time. I bought these wrist bands from boots (a chemist in the UK) that you leave on for the duration of the flight, apparantely they push pressure point on your wrist that suppress the vomit feeling. About 15 hours of using those and I was fine to go without them. Maybe they worked in a placebo like way but that's fine by me.