NEW YORK (MainStreet) — Quitting your job is never easy, even when you can't wait to get out the door. Even if you have something else lined up, you might not know how to go to work at a place that knows you're leaving. What's more, if you don't have a next job lined up, you might not have the slightest idea if you should even leave, no matter how unhappy you are. So when do you know that it's really time to leave your job? And what do you do when it is?

Is Your Job Impacting Your Quality of Life?...

"The one sign I think is definitive is the gut feeling of 'I don't want to go to work today,'" says Jayne Mattson, senior vice president of Keystone Associates in Boston.

And while everyone might have a little bit of dread on Mondays, your fear of work could be making your overall quality of life decline. "Are you having sleepless nights because you dread Tuesday, Wednesday and Thursday as much as Monday?" she asks.

Of course, everyone has times of not feeling great about heading to work. That doesn't automatically mean that it's time to leave. So Mattson suggests that you ask yourself when the last time you were excited about your work was. "What has changed since the last time I was excited?" she asks. This can help you to identify if you're just in a rut or whether or not it's time to move on.

You might have some degree of control over getting excited about your job again. For example, you might not feel challenged anymore. That means it's time to talk to your boss about getting some new tasks put on your plate that will make you feel engaged again. On the other hand, you might have a new boss that you just don't see eye to eye with on anything. That's a situation you don't have as much control over, so it's time to ask yourself if it's worth sticking around or if you need to cut your losses.

Are You Being Shown the Door?...

One reason that you might be unhappy is that you're being shown the door. Mattson says that if you noticed that you're not being included, that might be what's at play. Signs that you're being shown out are not being asked to come to meetings, not being involved in projects and being generally kept out of the loop. "Sometimes the perception of you changes," she says. "Your credibility has diminished. People are all of a sudden questioning things you've done."

If you find yourself in a situation where you're being kept on the outside, you owe it to yourself to have a conversation with your boss at the least and to look for a new job at the most. This type of situation is one that you might or might not have control over. You won't know until you put your chips on the table. Doing that will help you to figure out the best way to move forward.

On the subject of layoffs, Robert Hosking, executive director of OfficeTeam, says that in some cases, the writing might be on the wall. "If there have been layoffs or there are layoffs coming, people might front end their departure or even decide they don't want to stay if they get through it," he says. You might not be shown the door per se, but the difference is largely irrelevant.

What To Do When You Decide To Leave...

Mattson points out one of the best ways to leave your job is to be part of a round of layoffs that are happening anyway. "If you're really that miserable, I would find a trusted advisor and tell them you're not happy and ask if you could be part of the next round of reductions," Mattson says. Sure, the unemployment check will be nice to keep you afloat while you look for a new place to work. But there are other forms of outplacement help available to people unemployed through no fault of their own.

She notes that this can be a tricky conversation to have. "You could be labeled as not caring, when in fact you do care, which is why you're having the conversation in the first place," Mattson says.

You also want to start getting ready not just for your next job, but also your career moving forward, before you even leave. Mattson says you should set up networking meetings.

"Have information conversations with your network in a very confidential way to just start laying the groundwork," Mattson says. She says that you should keep the conversation overall positive. "Talk less about what's not working and more about what you want moving forward." She says you should stay away from badmouthing your company or anyone at it. You should also put the word out to hiring managers that you're looking. You might be able to get first rack t a job before it even gets posted.

Hosking says to ask yourself whether or not you even want to keep doing the same type of work. "You have to dig a little and ask yourself the right questions," Hosking says. That might mean that after you leave you're contemplating a change of career or even just refocusing whatever it is you do on a day-to-day basis. Sure, you might want to work in the same department, but doing something different, or in the same industry, but in a different department.

Most importantly, according to Hosking, you need to stay focused on your work and remain upbeat. "When you're there, you're there," he says. Walking away in the right way is important not only for the reference. But also because you never know where your next job is going to be. The people there might remember you. "You want people to say that you were great until the very end," he says.