There a lots of things you can do outside of the medication realm. The first and most fundamental is the least interesting: diet, exercise, sleep.

There's just so much research on the benefits of better diet, regular exercise and sleep quality and their impact on ADHD symptoms, you just can't ignore it.

Here are my mantras for diet -- something that you can alter and get immediate results with:

Sugar Sucks: it's a false friend of your brain cuz the energy it provides doesn't last.
Carbs Kill: especially simple carbs ("white" foods), which act like sugar in the ADHD brain.
Protein is Power: make sure you're eating a protein breakfast and snacking on protein (e.g. nuts) thru the day -- INSTEAD of sugar/carb snacks.
Omegas are Mega: get some quality supplements of fish/krill oil.

That's a start. Good luck to you!