The Best Man and Ushers
The choice of best man is easily as important as, if not more than, that of choosing the maid/matron of honour. To put it crudely, grooms are less likely to be well organised than brides, so it's often down to the best man to ensure that everything runs smoothly.
Never forget that there is a lot more to being a best man than merely making a funny speech. Although the groom's first choice may be his best pal from the pub or his hippy brother who lives in a commune in Thailand , you could be asking for trouble by selecting them. If offence might be caused through not asking such people, give them another key role in the wedding, like reading a poem, making a speech, playing or singing during the evening's entertainment, etc. Then choose a nice, dependable type who knows how to read a wristwatch and won't drop the rings down an open manhole.
Don't forget, too, that many grooms now opt for a best woman - a good friend, sister, cousin, colleague. Much as this may fly in the face of tradition, never forget that women are usually much better organisers than men and tend to get their priorities right ... or at least will have similar priorities to those of the bride!
Ushers aren't so much of a problem, provided they remain sober while ushering people into the ceremony venue and know a) where people should sit and b) where to guide people after the ceremony. This job is normally taken on by the groom's other friends, siblings and other (usually, but not exclusively) male relatives.
Clothes for the best man and ushers have moved on a lot since the traditional days of the dark suit, morning suit or dinner jacket/tuxedo. Although those are still very much in circulation, male attendants can also be booted and suited in lighter colours and different designs. Much depends on the groom's individual preferences, as the best man and ushers' outfits should echo what the groom is wearing. Just bear in mind that it's a lot easier and cheaper to hire morning suits or tuxedos than it is to find six identical sky blue designer suits.
A last word about hired male outfits: don't leave it until the day before the wedding to pick them up from the hirer's premises. If a mistake has been made you have very little time in which to get it put right. I know there are many funny stories about grooms wearing hats several sizes too big which cover their noses and best men in trousers so tight they deliver their speech in a squeaky voice. However I don't imagine you want people remembering your wedding for reasons like that.

