Dressing a man for a wedding always seems much easier than dressing a bride but the groom and his attendants need to plan their outfits to match in with the bride and bridesmaids outfits.
Many grooms are not afraid to express their own style and shouldn't worry about breaking with tradition.
The traditional morning suit is somewhat formal but always looks impressive. Many grooms prefer to wear suits but their attire will be dictated by the venue to a certain extent. If it's a beach wedding then shirts, shorts and jandals may be more suitable.
The groom usually wears something to distinguish him from his best man and groomsmen. They might wear the same suits but different coloured shirts or perhaps a differently styled jacket.
If the outfits are being hired they will need to be booked well before the wedding. You may want to help coordinate all their clothing and check the accessories are all ordered. When the garments are picked up from the hire shop check everything is there as ordered - there's nothing worse than discovering you have the wrong size or are missing a waistcoat just hours before the ceremony.