Earn What You Deserve at Your Job
You have to first distinguish at what point you are being offered a salary in the negotiation process:
1st situation is where you have not yet been selected for the job, and the employer is giving you an indication of the salary range. Remember to delay firm comments as much as possible and request more information about the job responsibilities. This helps you evaluate the job more carefully, and gives a positive impression to your prospective employers in that you do not focus only money.
2nd situation is where you have been selected for the job or career, and you and the employer are now negotiating your salary. When this takes place you need to start fighting hard for the best possible deal that you can, within reason of how much you can produce at this career or job.
If you are not sure which situation you are in then ask, “Can you clarify if you are making an official offer or if you are just discussing the salary range for this position.”
Ask the employer when you need to get them an answer. Tell them that you are honored by their offer and will give it very serious consideration, but that you need some time to get back to them. Don't accept the offer immediately. Then use that time to research the salary range of similar jobs in your industry. You can talk to the internal staff of your prospective employer or research and collect information from recruiter firms and local employment research centers.
Remember, they have a lot of candidates to consider, and the fair market price is the most important element in their calculations to determine an acceptable salary range for the job.
How should you put this offer to your employer? Every case is different, but always thank them and always indicate that based on your skills and experience, you are open to negotiate a mutually-agreeable solution.
Remember to use the words "open" and "negotiate" in your discussion. It signals that you are amenable to further negotiation. This prevents a scenario where you scare away your employers by appearing closed to discussion.
Most people don't want to negotiate salary. They're afraid that they will lose the offer. The fact is, an employer takes a lot of time to select a candidate before they make an offer. Once they have made it, they are less likely to change their mind over a question of money. If you reply with a counter offer, it might be annoying to them, but they will consider it.
So be brave!