Here are some tips for getting 100 mpg from a 2008 Toyota Prius (That’s right, 2008!).
1) Hit the Reset button.
2) Be sure you are in “D” and not “B”. “B” is for going down long hills.
3) Inflate to 42 PSI front, 40 PSI rear.
4) Maximize coasting/lower speed driving.
5) Minimize accelerating from full stops (for example, at traffic signals).’
I’m still experimenting, but today I found that it is better to quickly get up to speed from a full stop and then coast than it is to slowly accelerate. I need to verify that in a few more conditions.