Just like the bridesmaids, groomsmen generally have a few key tasks or groomsmen duties they traditionally fulfill. Take your role as groomsman seriously, after all, you're helping one of your best friends through what can be a very nerve-racking day.
Everyone loves a good party and even though planning the bachelor party is, traditionally, a best man duty, that doesn’t mean the other groomsmen can’t lend a hand. If you all work together, it’ll be a night or weekend you’ll never forget. If you aren't great at planning, a good gesture would be to chip in on funds towards the festivities.
Make sure you have every piece of attire before leaving for the groom suite or venue. You don’t want to forget your necktie or shoes at home or back at your hotel. Once the wedding day arrives, you’ll get dressed with the groom, share a toast, and likely take a few pictures while his significant other is doing the same.
One of the main duties of the wedding party is to keep their friend or family member calm and collected before and during the ceremony—so groomsmen are tasked with the groom. You may not always believe it, but grooms can get nervous in the hours leading up to their wedding, so groomsmen should try and keep him relaxed in the hours leading up to saying "I do".
If the couple has not asked anyone to be ushers, it will be your job as a groomsmen to help guests find their seats. Traditionally, the bride’s family sits on the left while the groom’s family sits on the right. So it is best to know the guests attending and allocating them to seats best suited to them.
The groomsmen and bridesmaids are usually the first to dance, after the newlyweds and their parents. So, don’t be shy. If you look like you’re having fun, everyone else will soon follow!
As the night draws to a close, make sure the couple is properly sent off to the hotel or off to their honeymoon. The groomsmen (and bridesmaids) may also want to stick around to make sure any important items (like gifts) have been collected.