On your television's handbook specifications page it shows two power consumption figures: one for ON when in use, and the other for STANDBY. You'll see that when in Standby it is using less power than a bicycle headlamp.
Over a year that is still a few of ££ of electricity so it's worth turning off and not leaving it in Standby overnight or when you are out.
The television set will not lose its tuning or set up information if you unplug it overnight. But it is better to use the socket switch rather then actually pulling the plug. There is always a risk of mechanical damage sooner or later if you are groping around behind a telly, or grovelling on a skirting board, trying to push a plug in. Find the tv power switch and use that instead (if it's on the side or just "around the corner" then put a small label on the front to show where it is).
Tv sets and video recorders are very good at memorising their configuration stuff, and some tellys can retain it for a few months without any power supply.
Instead of pulling the mains plug every night you should turn the appliance off at the mains on/off switch on the television itself. This will cut the power supply and so it consumes nothing. But it has the advantage that it's usually easier to reach this switch than the mains socket, and you won't risk damaging the plug.
If you are using an extension lead with switches on each socket of the "bar" then you can use these rather than pulling the individual plugs. But remember that if you switch off the mains socket that the extension lead is using then you will have removed power to all of it so you don't need to turn off each individual one on the "bar".
If your electricity bill is very huge then it's not likely that your television is doing this. Even a 50" telly doesn't consume more than a couple of 100W light bulbs, and it's only about 15-20W when on standby.
Most of your electricity consumption is by appliances that generate heat: cookers, hobs, electric fires, immersion heaters, electric shower heaters, and similar.
The next largest consumers are motors: freezers, fridges, washing machines, dishwashers, tumble dryers (note that the washing and drying machines also have heaters so they really suck up electricity when in use). A freezer that has lots of empty space will consume enormous amounts of electricity trying to freeze the air, so always keep yours full (even if it's only rolled up newspaper).
Old fridges also use more electricity because their pumps become inefficient.
Make sure that you always turn off lights. A lot of people are bad at this and turn on a light without turning it off again when they've finished what they're doing. Leaving lights on in empty rooms will use substantial amounts of electricity that will show up on your quarterly bill. The same applies to outside lights: unless they are actually being used by someone to navigate around your garden you should turn them off. (security lights should always be PIR operated).
Computers can use very significant amounts of power even when left "idling". An ordinary PC and its peripherals can consume the equivalent power of a 300-750w electric fire, that's a lot of "juice" over a day. So always turn it off if it is not doing something, or when you've finished with it unless you will be returning within half an hour. They don't mind being turned off and restarted.