Yesterday I was listening to a friend of mine lament about a new co-worker of his. Apparently, the 17-year old just graduated high school and was on his third day at his very first job.  Here are the impressions the teenager already made upon his manager and co-workers.

1.  “Joe” is on his cell phone all the time. In front of customers and his manager. He thinks nothing of chatting it up with his friends while he’s on the clock.

2. He goes 30 minutes over his lunch break.

3. His friends have come by to hang out with him.

4.  He left a mess behind in the kitchen.

5.  He takes shortcuts or worse, doesn’t complete assigned tasks.

My friend remarked that he doesn’t think Joe will be a very productive employee. That may or may not be true. Joe could be oblivious to workplace rules. That’s why most companies hold orientation and spell it out to all new hires. He could also be testing the waters to see what he can get away with.

Regardless, everyday is your job interview, and Joe is failing miserably. While it’s the company’s job to let employees know what’s acceptable and what isn’t, it’s in every worker’s best interest to seek out these rules on their own to avoid sending the wrong impression. So here goes.

Turn your cell phone off and leave it in your purse or a locker. You can check it on your break, but while your at work, your full attention should be on your employer. Give your babysitter your work phone number for  ’emergencies’ only.

Don’t exceed your allotted break time. Your co-workers will take notice and they will resent you for it. Especially if you’re getting paid for it.

Your friends can come by if they are customers. But they can’t hang out. Bringing people in who add revenue is good. Sucking up space and time is not.

Leave your personal problems at home.  The business has enough problems of its own, and you’re being paid to help solve them. Your co-workers don’t need to hear the dirty details of your dysfunctional family. Nor do they want to.

Clean up after yourself. This includes the microwave. And don’t cook popcorn. When it smells good, everyone is jealous, and when you burn it, everyone will hate you for the lingering smell for weeks.

Don’t use the computer for personal use. That means  checking personal emails, surfing, Facebook, auctions, recipes, etc. The same goes for the fax and copier. Did you know that your boss can check the hard drive in the fax/copier/printer to check out everything you do that interfaces with that machine? Do you really want her reading your tax returns?

Be presentable. Casual Friday is not wrinkled t-shirt day. Use an iron, or hire a dry cleaner to take care of it for you.

Most of these mistakes I’ve made myself and learned the hard way. Take heed if you want to keep your job and advance your career.