you will consume more electricity switching the air con on and
off.
When you switch on an air con. there will be a sudden spike in the
current used to start up motors in the aircon. THe current will
only stabilise like after 3-5 mins of use.
But if you switch it on and off, your aircon will need to work
harder to keep the room cool.
Whereas if your aircon is constantly on, the room temperatuer will
be regulated easily, then the motor in the aircon can switch off or
slow down (depending on your type of aircon)