Bargaining is usually done after you have been offered a job. Be very careful not to discuss salary before it presented by the employer.
Do not specify salary requirements in your job application
Even if it says in the ad to indicate your salary request, do not include it. You do not want your application to be disregarded because of your salary expectations. Also keep in mind that It is very difficult to specify salary before you have considered other conditions and benefits involved in the job.
Wait with negotiations until after you've been offered the job
Once you have been offered the job and it is time to negotiate, find current wage statistics for the job and the industry so you know what is reasonable.
Get the employer to specify a salary range
During the negotiations, it is important that you try to get your employer to set a salary range they expect for the position first, before you say what you consider to be reasonable. There are studies showing that the first person to enter an amount in a negotiation is usually the one who "loses." By asking the employer to name a salary range first, you avoid losing because they must come first with a bid. When the other party in the negotiations suggests a salary range, it is up to you to argue why you should receive the upper part of that range.
Other benefits and conditions
What are the work hours? Is there flex-time? Does overtime compensation apply? Are health benefits included? How many weeks of vacation are there? Are there any other benefits or conditions? It's important to have the answers to all of these questions before entering salary negotiations. Keep in mind that it is sometimes it is easier to negotiate for more benefits than a higher wage.
See to it that you have your negotiations written into your contract.