Keep it as small as possible. It used to surpirse me what a helo pilot would take compared to a fixed winger to do what amounts to the same thing. When private flying I used to have a headset bag and a kneeboard. Chart and plog on kneeboard, wallet and licence in headset bag. Now I'm a CPL, just a bumbag with wallet, chart, licence and passport, and a "brain" in the pocket of the flying suit. The brain is an A5 clear pocket folder with lists of frequencies, local airfield info and one or two other bits and pieces. KISS