how to improve fuel economy (chevy s10)?

ive got a 1997 chevy s10 2.2L 4banger.

i get decent mileage already. but who doesnt like saving a few bones?

also, nitrogen in tires instead of regular compressed air? true of false?

thank you

the only real gas saver is your foot, if you floor it all the time, wont matter
air filter
fuel filter

and nitrogen, true
but i wouldnt do it
less traction..