Assist the bride in getting into her dress and makeup
Ask if the bride needs anything (food, water, etc) all the way up till the time she is walking down the aisle. She will really appreciate it!
Assist the other bridesmaids on where to go and timing, especially if they show up late.
Help make sure the bride has privacy if she needs some quiet time before the ceremony.
Be the witness in the signing of the marriage license which is an honor!
Assist the guests to their seats and be social prior to the wedding. The guests love to see the bridesmaids and groomsmen out and about.
Take some deep breaths and walk slow when you walk down the aisle since it is common to speed up. If a groomsman walks down the aisle with you, make him refrain from talking or fooling around.
Always look for the unexpected since it is common for the most uncommon things to happen (i.e, something falling down at the alter). If you are close enough, fix what needs to be fixin so the bride, groom and their families can focus on the ceremony.
If you are single, make sure to mingle and have a great time at the party! It is mandatory to catch the bridal bouquet 🙂
If you are with your partner, make sure to dance and socialize since it means a lot to the bride and groom (when they have time to sit down) to see their friends having and creating a good time for themselves and the other guests.
Last, but not least, Provide moral support and be a great listener throughout the process since it is a very wonderful and “positively” stressful time for your friend. You can really make the difference!