I used a change-over relay for my generator, with a 240V AC coil. The coil is connected to the generator output - so when you start the generator it automatically switches over to that supply.
As it's only a 2KW generator, it only feeds part of the house - all the lighting circuits, the central heating electrics, and the downstairs ring main. Which includes TV etc. and the Microwave in the kichen.
Obviously you need to be aware what can and cannot be plugged in while the generators running - but there's nothing normally on it's circuit which it can't handle.