Quitting your job isn't something you should do on a whim. You might hate your boss or be offended by something that has happened, but you should still step back and make sure you have a plan. Even during the current time of historic or near-historic low levels of unemployment, it's not always easy to find another position quickly.
Because of that, it's important to approach leaving a job rationally. You should never quit in a moment of passion or emotion. That might be satisfying, but it's almost always going to be a short-lived pleasure.
Before you walk away from gainful employment you should make sure you know what's going to happen next. That may not include having another job lined up, but you should at least consider the following checklist.
1. Can you afford to quit?
Do you have enough money in the bank to cover your expenses while you find a new job? Ideally, you will have at least six months of reserves in an emergency fund. That number can vary depending upon how much money you were making, but it's important to know how much money you will need each month to get by once you are no longer working.
2. How easy will it be to get a new job?
Do you work in a high-demand field? Is the type of work you do readily available in the market you live in?
The answers to those questions should impact your decision whether to quit or not. If you work in a field where finding a new job won't be easy, it's not smart to quit without having a new position lined up. The same is true if the amount of employers in your line of work is limited in the market you live in.
3. Are you being rational?
Sometimes people decide to quit due to a moment of emotion. Maybe you did not get a hoped-for promotion or perhaps there was another slight that angered you.
Take a step back and consider whether you are making the correct long-term decision. If you are not, be willing to back down and stay in the job or at least stay for a while as you see how things work out.
4. Did you talk with your boss?
Many work problems are solvable. Maybe you want to transition to a different type of work or perhaps you want to move into management.
Before quitting you should discuss your desires with your boss. He or she may be sympathetic and willing to work out a long-term plan that gets you where you want to be.
Be rational and measured
If you ultimately decide you are going to quit your job it's best to do so rationally and not from a place of emotion. Quit professionally. Don't storm out in a huff or walk out in anger.
Ask for a meeting with your boss and resign politely. Give proper notice and do everything you can on the way out to leave a good impression. That may be difficult and distasteful, but it's the right thing to do and leaving the right way will be noticed and appreciated by your coworkers (and probably your employer, too).