As a wedding guest, you may be stressing about what to wear, or you might not care at all. If you know exactly what to wear, then you don’t need help from this article. To the unsure or fashion-challenged: There’s no need to stress.

You’re a guest, not even important enough for the wedding party, so making a grand statement is not required and really not desired. If you’re one who doesn’t care whatsoever, you could show up looking like Nick Nolte circa 2002, or even worse, turned away without the free meal and open bar.

Bonnie Rosa, owner of Perfect Events in Des Moines, shared some rules of thumb for the wedding guest in doubt.

The first and most obvious rule is to never wear white, even if the bride chooses a nontraditional color. Only shirts on men and sometimes women can be white in a wedding guest’s outfit.

The next most important thing to avoid is shorts. Even if the couple is getting married in scuba gear underwater, the guests wait on land in anything but shorts.

“It’s almost always the single guys that come in looking like the beach bum,” Rosa said. “I’ve looked at them and just said, ‘Oh, my god. What were you thinking?'”

Shorts are never appropriate, she said, no matter what type of wedding the invitation implies.

The next and most simple tip is to think about the type of wedding. It’s as easy as reading the invitation. The time of day, the location and the dress code are all likely right in front you. Is it a barn wedding? Then jeans, boots and cowboy hats are likely appropriate. Is it a country club wedding? Then avoid the country look; it’s not a trick.

“Many clubs and venues have dress codes,” Rosa said.

“I’ve known men who have been turned away from a country club wedding because they didn’t have a tie,” she said.

Women, she said, are less likely to show up looking disgraceful. This could be because women are “more in-tune to what’s in,” or because “they’re trying to impress a guy or get a dance.”

Because single men might also choose to impress, Rosa gave one over-arching rule. When it doubt, she suggests calling the venue, the bridal party or the wedding planner to tell you what to wear. If you still can’t decide between manpri’s or jeggings, follow Rosa’s final and simple tip.

Black is always appropriate and usually elegant.

Women can get away with a simple, black A-line dress at any wedding event. For a beach wedding, pair it with flip-flops, she says; for a cowboy wedding, pair it with cowboy boots. The same goes for black pants on men.

“It’s easier for girls because they can change it up with shoes and jewelry,” she said.

For guys, the big question is jacket or no jacket. Generally, if it’s outside in July, no jacket. If it’s formal in December, jacket. If it’s casual, no jacket. If it could go both ways, jacket.

Theknot.com has a quick and painless way to tell wedding guests what to wear. If the invitation includes a dress code, choose its equivalent in the “what should you wear” tool, and it will give fool-proof and open-bar acceptable outfit ideas.