Changing a socket looks simple and in some cases it is. The point is knowing where the line sits.
First, kill the circuit
Switch off the breaker and confirm with a voltage tester. Turning off the wall switch is not enough, because the cable stays live.
What you can do at home
Replace a socket or switch with an identical one, when the cables are in good condition and clearly identified. Photograph the connections before you take anything apart.
What you should not do
Spur new sockets off an existing one, move circuits, work inside the consumer unit, or touch old fabric-sheathed wiring. This is not about skill, it is fire risk, and your insurer may refuse the claim.
Signs of tired wiring
Warm sockets, a burnt smell, plugs that wobble, breakers tripping always on the same circuit. None of that is fixed by changing the faceplate.
Extension leads are not a permanent fix
An extension lead behind the furniture for years gets warm and collects dust. If you need more sockets there, you need a new circuit.
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