Buddhist Wedding Ettiquette 101

A Buddhist wedding ceremony has its own rules of etiquette.
Buddhists consider weddings to be civil ceremonies, not religious occasions. A wedding is thought to be a matter of the heart rather than a matter of the soul. A Buddhist is allowed to marry a person of any religion so long as that person is respectful towards the Buddhist's beliefs, and so a Buddhist marriage ceremony is largely based on the local culture and customs. If you are invited to a Buddhist wedding, the couple should let you know if there will be any "audience participation" moments expected of the guests but in general there are few hard-and-fast rules of etiquette.

Who May Attend:
You may be of any religious affiliation and still be welcome at a Buddhist ceremony as long as you are respectful of the Buddhist beliefs and customs. You will not be asked to partake in any rituals or prayers. You should be very polite to the monks, as you would be to any spiritual leaders whether you share their beliefs.
What to Wear:
You may wear whatever you would wear to any wedding; there are no restrictions such as in other religious customs. Wear what is appropriate for the weather, the occasion and the venue. The brides or grooms will probably dress up a bit, but they too may wear anything they choose (if it's not too revealing).
Where You'll Be:
Since most Buddhist weddings are intimate occasions and only family and very close friends are invited, many of them are held in private homes, yards or outdoor venues. If the couple lives near a temple, they may hold the ceremony in the shrine room or on the grounds. Either way, guest etiquette is the same: quiet deference and respectful observation.
Watch Your Feet:
If the wedding ceremony is held in a temple, you may be asked to remove your shoes before you enter the shrine room. It is also considered disrespectful to sit so that the soles of your feet are facing an image of the Buddha, so be aware of this when crossing your legs or kneeling.
What to Expect:
Most ceremonies are somewhat free-form and will last about 30 minutes, with the couple exchanging vows to be faithful in their duties to one another. The monks will chant from sacred texts, but there is no call-and-response, the guests and couple are expected only to listen, and there is no other music. Unless it's posted otherwise, it's permissible to take photos or video of the ceremony if you can do so without disturbing anyone. After the ritual you won't throw confetti, bird seed or anything else at the couple (it's considered impolite), but will proceed with them to the reception---which will probably be as unique as the newlywed couple themselves. And all YOU gotta be is YOU... that's WHY you were invited...just saying...