What do you need to change your name on?
Driving Licence - To change the name on your driving licence you need to complete the relevant form from the DVLA and send it back along with your old licence (paper and photocard) and your marriage certificate. It's free to change your name on your Driving Licence unless you are missing a part (e.g. the paper part). You will then have to pay a fee to cover the replacement of the missing part. Visit the Gov.uk website here for more information.
Mortgage - To change the name on your mortgage usually you just need to pop into your branch for them to photocopy your certificate. There may be a fee to change your name depending on your mortgage provider so it may be worth calling them in advance to find out what needs to be done.
Memberships and store cards - It all depends on the company's policy for this as some are happy to accept a photocopy, some will accept a scanned and emailed copy of your certificate and some will want to see the original. Go through your purse and make a list of all the companies you have accounts with. Some you might not need to change (like your nectar card for example) but for others like store cards you will need to check with the company, especially if there is credit involved.
Travel Insurance - If you're planning on taking out travel insurance for your honeymoon, make sure it matched the name on your passport. If you already have travel insurance and are changing the name on your passport in advance, call the company to check whether you will still be covered if the name on your policy does not match the name on your passport. Make sure to also check the name on your EHIC card or get one if you don't already have one. Make sure you use the free service via the NHS website here. EHIC cards are free. You DO NOT need to pay a penny for one so don't get caught out.
Work - Make sure to let your HR or Personnel department know in advance that you will be changing your name. They'll let you know what you need to do. You may also want to contact your IT department to get them to change your email address (if necessary). If nothing else it may reduce your inbox while people get used to your new last name!