Negotiating your salary can be a slippery slope - not only for seasoned employees, but for those who are just starting out in a new job as well. All pros and cons should be carefully weighed before taking any action at either point in time.
If you're just starting out:
Potential job candidates are strongly advised to never enter a salary figure into any space provided on a job application - unless required. If the salary that the employer is prepared to offer is lower than what a candidate has entered, the potential employee may be deemed to be more interested in money than how or what he or she can contribute to the company's profitability. On the other hand, if you put a salary amount lower than what the employer has in mind, you could be settling for less than you deserve.
Candidates are also advised not to broach the salary issue, but rather to wait until the interviewer mentions the topic. Bringing up salary too soon can make you seem money-hungry. Once a figure has been voiced by the interviewer, you should attempt to display the best poker face possible. Facial expression can give the interviewer a wrong impression.
Prior to the initial interview, you should do your research via websites like Glassdoor to learn as much as possible about what other comparable companies in the area are offering for the same position.
If you're been employed for a while:
For seasoned employees contemplating a salary raise request, establish the minimum figure that will be acceptable to you. During tough economic times, especially in the USA, 80% of companies have built-in wiggle room in terms of the company's bottom profit line and financial stability.