Getting dressed for work used to be pretty simple for administrative professionals and other office workers. Men would put on a suit and tie, and women would dress in a tailored dress or a skirt suit. No matter where you worked, there wasn’t much variation.

These days, though, it’s not quite as straightforward. Office dress codes differ dramatically depending on your region and your industry, which can make choosing an outfit for work a bit confusing. A recent OfficeTeam survey backs this up: 56 percent of workers surveyed said they prefer more relaxed dress codes, but 41 percent admitted they’re at least sometimes unsure about whether a piece of clothing is appropriate. In fact, nearly half (48 percent) would choose to eliminate uncertainty altogether by wearing a uniform to work.

The confusion is understandable, given that 23 percent of those surveyed said their company dress code isn't always clear about what kind of clothing is acceptable. Still, selecting the right workplace clothing is particularly important for administrative professionals, who often serve as the first point of contact for their team, department or business. The way you present yourself can affect the impression a customer (either internal or external) has of the group you represent.

So what are the rules about dressing for work these days? Read on for 12 commonly asked office attire questions — and their answers:

1. Why do companies even have dress code policies?

In offices where employees often interact with clients and customers, a dress code can help a company project a certain professional image. Some firms also believe a dress code can increase professionalism in the office. Still others have dress codes for safety reasons. (In certain workplaces, like factories or medical offices, open-toe shoes and loose clothing or jewelry can be dangerous.)

In any case, if your company has a dress code, you need to abide by it. You should have received a copy of the rules during your new-hire orientation; if not, ask your HR representative where you can find them, and make sure you read and understand them.

2. What does my office attire say about me?

You’ve probably heard the saying, “Dress for the job you want, not the job you have.” It’s good advice, because whether they mean to or not, your coworkers and managers will judge you by your appearance. If your office attire is polished and professional, you’ll typically make a good impression. But if you always look sloppy and unkempt, your colleagues and supervisor might think you’re not serious about the job.

3. What is ‘business formal’ attire?

Sometimes known as boardroom attire, this is the most formal workplace dress code — the kind you might find in a law firm or financial services company.

For men, it means suits in a dark color, with a conservative shirt and tie, and brown or black oxfords. Women can wear a skirt or pantsuit with a shirt or blouse, stockings or pantyhose, closed-toe pumps and conservative accessories (such as pearl stud earrings and a traditional watch).

4. What is ‘smart’ attire?

It’s a step down from business formal, but it’s still pretty conservative.

Typically, it means men should wear a suit or dress pants with a collared shirt, a jacket, and loafers or oxfords. Ties are typically expected. Women can choose a tailored skirt or slacks, a blouse or shirt, a jacket or cardigan, and closed-toe pumps or flats.

5. What is ‘business casual’ attire?

Typically, “business casual” means collared shirts and slacks for men, with a pullover sweater or a sports jacket and loafers or oxfords. Ties usually aren’t required, but some men choose to wear one anyway. For women, separates like skirts and tailored pants, with blouses or shirts and closed-toe pumps, flats or loafers are good choices.

6. What is ‘casual’ attire?

In some offices, this means T-shirts, jeans and sneakers. But in most workplaces, "casual" still means khaki pants, cotton slacks and skirts, collared polos or blouses, and pullover sweaters or cardigans.

Sometimes, denim is acceptable; if you do wear jeans, make sure the cut and color are conservative. There’s more leeway with shoe choices in casual businesses, too: Loafers are fine, and sneakers and sandals are sometimes allowed, as well.

7. What’s the rule for casual Fridays?

This is different in every office. In some places, it means you can wear jeans; in others, it means you can take off your tie for the day.

Make sure to get a good explanation from HR of what’s expected. If you have any questions in your mind about what you’re wearing, or feel uncomfortable in the outfit, change.

When OfficeTeam surveyed senior managers to ask about the most common office-attire mistake, 47 percent of respondents said overly casual clothing was the No. 1 error.

8. How should I dress for summer weather?

Even though it’s hot outside, you still have to wear proper clothing. Look for suits, skirts and pants in breathable fabric, like cotton blends and linen. Also, try to dress in layers, if possible. For example, women can wear sleeveless shells with cardigans or jackets that they can take off when they leave at lunch or at the end of the day.

Get our list of top 11 summer fashion faux pas.

9. What do I wear when it’s raining?

The key is to make sure you don’t arrive at work looking like you’ve been stranded in a storm. But you also don’t want to look like you borrowed your kid’s slicker.

If it rains often where you live, invest in a classic trench raincoat, rain boots, a hat and a well-made umbrella. If you wear your boots on your commute, make sure to bring shoes to change into when you get to work.

10. How should I dress for an interview?

You may think it’s awkward to show up in formal business wear if your interviewers are in casual office attire. But, truly, it’s never a bad idea to wear a well-tailored suit to a job interview.

If you know anyone at the company where you’re applying, ask about the dress code, and choose something that’s at least one step more formal than what most people wear. Whatever you do, don’t put on clothing that’s too flashy; you don’t want your outfit to be the thing that defines you in the hiring manager’s mind.

Read about do’s and don’ts for dressing for an interview.

11. What about tattoos and piercings?

Many businesses are getting more flexible about body art, particularly as it becomes more common. Still, it’s not a bad idea to take body piercings out (other than earrings) and keep tattoos covered up during interviews and when you first start a job. Then, watch your fellow employees. If you notice that several of your coworkers have nose rings or display their tattoos, feel free to do so, as well.

12. What are some absolute ‘don’ts’ for office attire?

It’s hard to find rules that apply at all workplaces, but most companies agree that clothing adorned with a logo (that means anything from Adidas to the Golden State Warriors) and flip flops are inappropriate. Never put on anything that’s torn, wrinkled or dirty.

You also want to make sure you’re not showing too much skin. In fact, 32 percent of senior managers in an OfficeTeam survey said this was the most egregious violation when it comes to office attire.

Here’s a good rule of thumb: If you’d choose the outfit for a nightclub, the gym or the beach, it’s not suitable for work.

Dress codes in today’s workplace can be baffling, and it can be hard to pick the right outfit. In general, dress slightly better than you think you have to, and always err on the side of caution. That way, you’ll never feel underdressed or inappropriately attired in the workplace.

View the SlideShare below to learn 10 common office attire mistakes — as shown by kids.