First: Know your worth. Offer aside, you should know what this position typically pays, and what experience you have that makes you more valuable. Dig around online to find out what similar roles pay and factor your own worth in the equation. Let the employer do the talking, but have this information handy in case you need it.
Next: Understand what the job will entail. Not all job descriptions are created equal. Maybe the employer is willing to pay more for a reason. Perhaps the job requires more travel than you'd like, or for you to put in extra hours. Know what you'll be getting in exchange for the salary, and make sure the tradeoff is worth it.
Then: Hesitate, even if it's a great offer. Don't feel like you need to accept the first offer the moment it's put on the table. Ask for some time to consider it. Most employers will expect you to take the night or weekend to think over a job offer and starting salary. Just don't ask for too much time unless you are prepared to lose the offer.
Negotiate for what you want. Depending on the company, there might not be too much wiggle room for the salary number. In this case, you'll need to put your creative negotiation skills to good use. Can you negotiate working from home one day a week? Extra vacation days or other perks?
Be confident when you counter the offer. Explain why you think you're worth more:
What to Avoid in Negotiations Focusing on your personal needs. Your personal circumstances for needing a certain salary won't get you far in negotiations. Employers pay a salary based on market value and don't care if the fair market wage doesn't cover your monthly expenses. Any salary negotiation should be based on solid research, not personal needs.
Asking for too many changes. Asking for changes in the salary, hours, benefits plan, etc. all at the same time could quickly lead to a revoked offer. Choose your battles carefully and focus on negotiating the most important aspect of the offer. If changes are non-negotiable, see if there are other parts of the offer you can modify.
Taking the offer personally. If you're offered something that doesn't meet your expectations, don't take it personally and burn bridges. If you counter offer and explain your position with valid reasoning, and the employer can't come up with something that meets your expectations, then simply move on. You were the finalist selected for the position, and perhaps in the future the company will have another opening that fits your expectations. Or, you may reconnect with one of the interviewers at some point in the future.
Lindsay Olson is a founding partner and public relations recruiter with Paradigm Staffing and Hoojobs.com, a niche job board for public relations, communications, and social media jobs. She blogs at LindsayOlson.com, where she discusses recruiting and job search issues.