All electricians in the UK are required by Law to stick to the building regulations in place so they can carry out work in people’s homes or business premises according to the strict rules.
There are a few Government approved schemes that electrician belong to and you will be able to check that they are legitimate by contacting the body that they are associated with. Once you have check this, you will have peace of mind that you are protected from certain things and that the work carried out will be to a professional standard.
To find a good electrcian, you can use a search engine and type in something on the lines of electrical contractors in North London if you are in London or electricians near me. Most people use word of mouth to find an electrician from a friend or neighbor. Another way is to search online adding the area that you are in. There are other sites like trust a trader where qualified electricians are on there with the area that they operate and ratings, feedback and reviews.
If you are unsure, you are quite entitled to ask to see the paperwork in person as proof and ask questions if it is necessary. All reputable electricians will let you see this without question. If this refused, then it would be wise to look elsewhere.
It would be advisable to get a reference as well from a past customer that was happy with the service provided.
Once you have chosen the person that wish to complete the job, get a quote from them before work starts. This will make it clear on how much you will pay once complete. Agree this with the contractor and so there are no nasty surprises at the end of the job. This way everyone knows where they stand.