Forget the aviator sunglasses and leather bomber jacket. However, you might want to dress in layers for the weather. It can be windy and cold on the ramp.
Have writing stuff (like a small or mid-sized notebook and pencil) handy to take notes. But don't stress on the notes, rather try to absorb what you can from your instructor.
You may wish to eat light prior to the flight, as that my minimize the likelihood of any motion sickness, which many initial primary students may experience from time to time.
Be ready to absorb material, and understand that at the first lesson you don't have to remember everything in detail.
Here's some of the stuff I cover on the first flight:
- aircraft documents, POH, checklist locations
- Doors, latches, compartments and pockets
- seat belts, windows and airvents
- overview on controls and control surfaces
- overview on electrical, vacuum and pitot/static systems and instruments
- preflight and checking engine oil, belts, etc.
- starting engine (instructor runs controls for this flight)
- radio communications (usually done by instructor for this flight)
- taxi aircraft, started by instructor, then done by student
- takeoff demo with student following through on controls
- trim and control forces
- climb (done by student)
- cruise power settings (demo first, then student does)
- turns (demo first, then done by student)
- some configuration changes, like flap extension (optional)
- return to airport (instructor doing most or all of communications)
- approach and landing (instructor takes over at some point)
- checklist usage
- postlanding taxi by student to ramp, instructor assisting
- postflight procedures, and securing aircraft
- identifying study materials, laying out the next couple of lessons, etc.
Expect that you will be operating the flight controls 50 to 90 percent of the time.
I book primary initial flights for 2 hours, and later flights for 90 minutes. Times differ depending upon school, FBO, private or club aircraft, and servicing details.
You are essentially hiring a tutor, and if you think the chemistry isn't right, you can always switch to a different instructor. Instructors have different styles and some flex their styles to their students needs better than others. So if the chemistry doesn't seem right, just go with it for a flight or two, and see how it works out.