On short rides 2 hours and under I just drink gatorade and carry at least one gel pack just incase.
Gel packs do tend to be a bit much though and have just recently got some chewable gel shots.These come with about 10-12 chewable things in a pack so you can adjust how much sugar you are getting.

For longer rides I like to snack on trail mix regularly,with this you get some carbs and some protien and fat to help slow the carb absorption.This work for me for several hours but I still need to stop and eat a regular lunch or something.

Really the best thing to do is figure out what works for you.In the mean time carry more of those gel packs than you think you will ever need just for emergencies.