Wats are used to lots of visitors, often by the busload. That’s sort of the point of them, actually. Naturally, many if not most of their visitors will be practicing Buddhists, but they welcome non-Buddhist tourists too, although not without a few basic behavioral expectations.
As a non-Buddhist, it can be a little strange at first to tour an area where actual religious worship is going on around you, especially at first. But push through that initial discomfort and you will find visiting Thai Wats a lovely means of getting to know the customs of the country.
Clothing: men and women alike are expected to cover shoulders and knees. I know—it’s hot and humid, and they want you to dress for fall? Yes. Thai culture in general is fairly conservative, so if you are deemed to be showing too much skin, you will be asked to cover up. Most Wats offer loaner shawls you rent or borrow to drape over yourself.
Shoes: take them off before you go up the stairs to the sanctuary. Some Wats have shoe racks, others just have neat rows of lined up shoes marking the spot where you slip them off. On days we were likely to visit a Wat, I wore little half-socks to pad around in, but barefoot is fine too.
Now that you’re dressed properly, wander around and soak it all in. Many Wats are decorated with scenes from the life (lives?) of Bhudda. These are worth a look—see if you can figure out what’s going on in the picture. There will be statues of Bhudda in many poses: reclining, holding up a hand. Or many hands.
There may be other statues of other gods, or disciples of the Bhudda. Buddhism in Thailand is an aggregative religion, unafraid of incorporating new elements. Each Wat will have its own flavor, which makes for an interesting variety. After a while, you will see recurrent themes and maybe even recognize some of the characters.
You’ll also see dragons, called Naga, often on stair rails. These are gorgeous, and super Instagrammable. In general, the more beautiful the Wat, the more people taking selfies, posing for pictures and admiring the views. Picture taking is generally fine, even in the sanctuaries. But try not to photograph people at prayer, or the monks in general, without their permission.
Speaking of monks: they are everywhere in Thailand, but as you’d expect, doubly so inside a Wat. You can’t miss them in their saffron robes, with shaven heads and bare feet. Please try not to touch or bump into them. If you do, even by accident, they will have to undergo a purification ritual that I’m sure will not make them happy. (In fact, to prevent any accidental contact, they are even seated up front and away from the general public on planes and boats!)
Many Wats have Monk Chat hours, which I highly recommend. You can talk with them while they practice their English, and they’ll tell you about their lives as monks, what their plans are for after they stop being monks (most monks are short-timers) and give you a little Bhuddism 101. Don’t be afraid! They don’t bite.
A couple last words: when you enter the sanctuary, most of them have a little step you have to step over to get in. This is symbolic, so try to step over it instead of on top of it, if you can.
And last, while tourists are sort of exempt from the expectation of merit by donation, it’s always nice to leave a little something in the collection box. It doesn’t have to be much: a bag of rice for the orphans, a few baht in the collection box, or the purchase of a personalized leaf, prayer ribbon or roof tile—any of these will allow you to leave a little of yourself behind in a good way. And that’s what making merit is all about!