Firstly we need to start with some questions - grab a pen and paper and make some notes as you go. Draw a table and make columns for each Bridesmaid and fill in the answers. Beware : Honesty required.
Height (Petite, Regular, Tall)
You could give consideration to what colour they like wearing or what really suits them.
Lastly - are they particularly self conscious about a particular part of their body. This could be anything from their arms to a birth mark. You should know them well enough to be able to answer this.
The trick is not to give them what they want BUT to try and find a colour, cut and style which can be tailored to suit them all.
What would I recommend?
I would certainly recommend you taking your chief bridesmaid / maid of honour with you to show her the shortlist of dresses. Be it high street or from a boutique you can adjust dresses accordingly but you need another opinion. You should also delicately go through the list you create above.
I would go in with as much time as possible. It could well be that the dresses are only available part of the year (high street moreso) and once they have all tried on get them ordered / bought! I very nearly lost out with mine.
You should look after the dresses for safe keeping - it could well be they would like to loose a few pounds for your wedding so they should keep trying it on so they feel comfortable.
A couple of months before encourage them to start underwear shopping - this can take longer than you think. Take the dress with you so you can double check it is the right purchase.
If in doubt make them get the bigger size! Accept nothing less. Its better for it to fit there and then than for them to promise they will fit into on the day. You can always get it taken in.
Lastly, remember that you don't have to get them to all wear the same dress. There are many companies which do the same colours with different necklines, straps, lengths so whatever you do - do NOT panic.
I would love to hear your thoughts on this - please get in touch firstname.lastname@example.org
Love Katie x