Stick it in "D" or "R" as necessary.
"EV" mode is useful for moving short distances, such as in and out of a garage, but on the road it can force the traction battery below the optimal level which means the petrol engine then runs longer to get back to the normal charge range.
Do not stress trying to keep the traction battery at a particular level, Toyota have spent millions of Yen on making hybrids work without too much driver intervention.
"B" mode, only use on steep or long downhill roads.
If you have Cruise Control, use it whenever possible, the system can adjust the throttle much better than you, so economy improves.
Once up to the lower speed limits (30/40) briefly lift off the throttle to encourage the care to go into electric mode, then gently re-apply throttle to maintain speed.
When slowing down, anticipate more and use a gentle press for longer to maximise regenerative braking.
Don't be surprised if your rear discs get a bit rusty, they only get used when the pedal is pressed pretty hard or below about 10 MPH.
You will notice that winter economy is significantly worse than summer, it likes to keep ITSELF warm and if you like to be toasty too, that will exacerbate the situation.
Air Conditioning use make hardly any difference to economy.
I have had 4 hybrids, all from Toyota/Lexus and the Yaris had the greatest variation from summer to winter economy.