The 19 Worst Mistakes Interns Make

statigr.am/lovelee12_We recently laid out the 15 ways you can make the most of your internship. But, as it turns out, there are also some easy ways to blow it.

If you really want to make a good impression and ultimately land a full-time job, you'll want to avoid these 19 mistakes:

1. Forgetting the pre- and post-internship phases. Before your internship starts, ask questions, take tours, and generally get to know the organization you'll be part of, suggests Kerry Schofield, a psychologist and the chief psychometrics officer at professional assessment and self-improvement platform Good.Co. "After your internship, follow up with thank-you notes; update your resume; and stay in contact with people you met."

2. Getting frustrated or complaining about being bored. Most internships start slow and build up, says Ryan Kahn, a career coach, founder of The Hired Group, and author of "Hired! The Guide for the Recent Grad." "Not all companies have a structured training program or welcome receptions for new interns - so be ready to roll up your sleeves and find opportunities to contribute."

3. Dismissing the small tasks. Know that some tasks are just a test, Kahn says. "Even if your first task isn't worthy of your talent or potential, jump right in and be enthusiastic. Remember every task builds upon the last, so if you do a mediocre job on the simple things, then there is no way your boss will help you step up to the big projects." You'll have to walk a bit before they let you run.

4. Ignoring instructions or advice. Even if you think your boss and colleagues are in the wrong, it's important to respect that they've been doing the job a lot longer and may know things you don't, Schofield says. "Not to say they're incapable of being wrong, but if you think that's the case, handle it diplomatically," she says.

5. Sitting back and waiting. "One of the biggest mistakes I see interns make is that they sometimes don't take advantage of all the opportunities in front of them," Kahn says. "If you sit back waiting for something to happen, nothing will. You need to be proactive, by making the most of your internship to get the most out of it."

He says you should volunteer to do something you think is needed. "Help a coworker, or ask for more responsibilities," he suggests. "And always show your willingness to put in the extra work."

6. Getting sloppy with email. "A work email shouldn't be written like you are texting your best friend, but many interns tend to forget that," says Morris Rishty, CEO of REAL Underwear. As an intern, it's especially important that you always proofread your emails at least three times before hitting send. "A poorly written email can show the boss that you have little interest in the position and aren't taking the job seriously."

7. Asking questions without first trying to figure out the answers on their own. It's a given you'll have questions in your new role, but instead of bombarding your boss every 10 minutes, first take a moment to think about whether there's any way you can find the answers on your own. "After this, if there are still some questions you simply couldn't get answers for, create a list to bring in to your boss," Kahn says. "This will show your ability to problem solve and be sensitive of their time."

8. Underestimating how time-consuming certain projects may be. "Be time-wise," Schofield suggests. "Don't take on more than you can handle."

As a rule, people underestimate how long a task is going to take, so when you're working out the timeline of a project, be generous in your time estimates, she says.

9. Taking criticism personally. Constructive criticism is all part of the learning process, and not everyone will be polite about it, Schofield explains. "Don't tolerate bullying or disrespect, but do grow a thick skin - that way you'll learn from your mistakes instead of repeating them."

10. Arriving late. Showing up late for work or to a meeting, shows you're not reliable and could leave a bad impression with your employer, Rishty explains.

11. Forgetting names. "It may be overwhelming initially - but this is one of the simple first steps to get someone to know and trust you," Kahn says. "Use a personal notepad to take notes on everyone you are meeting, this way you'll never forget their names."

12. Dressing inappropriately. While some offices celebrate Summer Friday or Casual Friday, interns still need to dress professionally, especially if they're going to be interacting with clients and high-level staff, Rishty says.

13. Not asking for clarification. If the requirements of a task or project aren't clear, ask for more details, Schofield says. If the task is deliberately open-ended to give you a chance to learn and show initiative, make sure you have all the information and resources you need before starting, and don't be afraid to ask for help or advice.

14. Forgetting to double-check their work. It's easy for an intern to quickly do a task to get it done, Rishty says. But it's imperative that you double-check your work before submitting it to the boss, since even small errors will make you seem sloppy.

15. Using their cell phone. Don't make personal calls. Don't text. Don't surf the web. In fact, you should just put your phone away during the workday so you're not tempted to use it.

16. Leaving projects unfinished. Not finishing an assignment shows your employer a lack of commitment and that you're not a hard worker, Rishty says. "Always finish your work before the deadline to show you have good time management skills and that you're committed to the job."

17. Taking too much time off. Every company has its own policy - but the experts say interns should refrain from taking too much time off for vacations, especially if the internship is only eight weeks long (or less).

18. Allowing themselves to be taken advantage of. Interns may work for little or no compensation, but the experience should be of mutual benefit, Schofield says. "If nothing else, you should be learning something. If you're not, don't be afraid to point this out. Be aware of your rights as a worker."

19. Forgetting to document your internship. Keep a journal or private blog of your experiences, and write a review for yourself afterwards, Schofield suggests.