1) Regular meter readings. Make sure you check every time you receive a bill, rather than relying on an estimate by your energy provider's estimate.
2) Change to online bills. You could save up to 10%.
3) Avoid prepayment meters if you can, and swap to a billed meter. Even if you have to pay to get one, it's probably worth it for the savings you'll gain.
4) If you're in financial trouble some companies offer special deals, which help ease any difficulties you might be facing. But don't just assume this will be the cheapest option - make sure you still do your homework.
5) Dual fuel (gas and electricity from the same supplier) is not always the cheapest option.
6) Monthly direct debit payments could save you 5-10% as companies are more confident that customers won't default and earn interest on any over-payments. Check any extra payments are refunded at the end of the year.
5) Swat up on how to lower your energy use