1) Do try on every style

I know everyone says this, but you really will be surprised by how different things look on you. And even if your dream dress is more Carolyn Bessette Kennedy than Glinda The Good Witch you MUST try on at least one big meringue number - just because they're SO fun to swish about in.

2) Don't invite Negative Nancys

If you're usually a bit of a lone wolf shopper (as I am) you too will find it weird that buying a wedding dress involves a group outing. Only bring positive friends and family who will give you good feedback. Good: 'You look great in that style, though I'd love to see how it looks with some little sleeves.' Bad: 'Holy muffin does that one come with head-to-toe spanx?'

3) Do beware the 'box of lies'

Lots of bridal boutiques will provide a little platform for you to stand on in your dress. The danger of this is you can a) forget you're not a 6 ft tall Victoria's Secret model and b) end up buying something you haven't actually moved around in. Bring a pair of heels (the shop usually has some but they might not be in your size) and mince around the place to get a feel for how comfy it is.

4) Do prepare for 'wedding dress voice'

This is what I call the reverent, softly-softly manner of speaking popular among bridal shop assistants. 'How does the dress make you feeeeeel?' 'Tell me about the person you want to be on your day.' At one fitting I went to there were four assistants who whispered around the rail of dresses like they were sleeping children. It's a little weird but you'll get used to it.

5) Don't forget to think about the actual day

If the wedding dress is so big you feel like you're lugging a duvet around after you then it's worth considering whether that extra weight will be much fun in the middle of a field on a hot August afternoon.

6) Don't buy a dress from a place where the shop assistants ask 'and how much weight are you planning to lose?' Because no-one needs that.

7) Do wear the right underwear

Nothing ruins the sheer lace top of a wedding dress more than a great big visible black bra strap. A nude multiway bra from Marks & Spencer and a pair of  spanx in the same colour – which are very helpful if you're planning to go slinky – should cover all eventualities.

8) Do book wedding dress fittings at bridal boutiques where they stock real people sizes

There's nothing worse than being shoehorned into a size 6 dress you can't even zip up. You wouldn't buy a £70 dress from Topshop if the only available size to try on was a 6, and odds are you're about to spend a lot more than £70.

9) Don't take pictures without asking

A lot of bridal boutiques have a very strict policy on taking photos (even though in theory if you wanted to copy something most designs can be found online anyway). This doesn't apply to dresses alone - I once got told off at a bridal show for taking a picture of a plate of biscuits without asking. That said, there are other great boutiques who will allow you to take as many piccies as you like: Katya Kayta Shehurina, Jenny Packham and Alice Temperley to name a few.

10) Do go for a designer who does in-house alterations

If you're spending over a grand on a dress, the designer should really provide their own in-house alteration service. That said - many don't. I've heard horror stories of brides whose wedding dresses have been sent away to be altered and come back totally botched. If they do the alterations through an external company, make sure you check out who they are, or otherwise take the dress away and find a seamstress you trust.

11) Don't stress too much about timings

A lot of boutiques will say they need 6 – 8 months to turn around the gown in time for your wedding, but if you're having a rush-job nuptials then designers like Alice Temperley will have samples available which can be altered in under a month. Whatever your wedding dress fitting timeline there's something out there for everyone, it's just a case of finding it.

Planning your wedding and not sure where to start? Don't panic! We've rounded up the best alternative weddings shoes as well as affordable and alternative wedding dress designers who won't make you look like a meringue. For wedding venue inspiration we've rounded up the wedding pinterest boards as well as affordable wedding decoration ideas. We've also collated some seriously beautiful wedding readings that will make your guests cry

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Got a wedding dress fitting story or tip of your own to share? Why tweet us at @InStyle_UK - we'd love to hear what you might have learned in the build-up to your own big day.