Anything other than changing a fuse of a lightbulb around the house electrical wise should be done by a professional as this type of work is extremely dangerous and can harm of even cause a fatality if you do not know what you are doing.
You will most likely get the odd electrical problem from time to time whether it is a light fault, or an electrical problem that would involve a complete re-wire job.
So when this situation arises, how do you find a professional that can do a competent job for you that is safe and is guaranteed should a problem arise in the near future?
A lot of people rely on the word of mouth method which is fine is the electrician is genuine but you should still research a little deeper so you get a qualified person.
For best results, a quick online search for an electrician in your local area will give you a long list of websites and as an example you should read through the SOS Electricians Website
The person in question should be professionally trained and you should ask to see credentials and any good electrician will happily show you. They should have a City and Guilds and be accredited by a governing body such as NICEIC, NAPIT or ELECSA.
Insurance is crucial because in the unlikely event of something going wrong, you will be covered for any damage caused which will give you peace of mind.