is there any methods/tips to save gas and not let the bike burn it up so quick?

Thats actually really good gas mileage. The best thing you can do is keep your RPM’s low as much as possible. Dont rev to high and you will maximize your gas mileage.

Thats good gas mileage. Dont drive like you are racing, and keep at the speed limit, thats whats going to save you the most gas.

That thing in your right hand is a control unit, control it for better mileage.
But you didn’t mention the bike under scrutiny. !?!?

If under 600cc’s and newer than 15 years old, a tune-up is advisable.

Walk

Use correct gear ratio for current speed/slope/road conditions, don’t lug it or over-rev it.
Keep an eye on tire pressure.

Don’t rev needlessly
Don’t take off from red lights, stop signs, etc.. accelerate slowly.
Let go of the gas way before you begin to stop.
Check Tire pressure
Clean filters

5 simple things off the top of my head

That’s pretty good mileage depending on what you ride.

As with any motor vehicle, riding slower, accelerating less quickly and keeping your bike in good tune will improve gas mileage.

Ride with the rpms in the torque plateau (all torque curves have a flattish level).

Use observation, the less time you are braking – the less you waste in regaining the speed, so instead of bombing up to a bend, braking hard, turning in and accelerating hard out, moderate your speed before you get close to the bend with the throttle, change down if that keeps the revs in the torque range, then take a smooth line through the bend. If you ride at a constant speed without too much variation you will improve the mpg.