This exercise is dreaded by many of us, because we simply aren't used to it. However with a tiny bit of practice and a few tips, negotiating your salary during a job interview will become as easy as 1, 2, 3!
Before walking into the interview room, you should know that the recruiter WILL ask you what your salary expectations are. Having a figure in mind before the interview will help you get a higher salary than walking in without any idea of what you will ask for.
Before the interview, make some research and enquire about the market's salaries in order to figure out what your value is. You can have a look at salary studies made by different agencies such as APEC or Urban Linker. Don't hesitate to ask people around you with a similar profile or experience what they earn.
If the interview went well, the question of your salary will naturally be brought up. A good strategy would be to let the recruiter mention it first : this will let you have an idea of the budget planned for your position, and you'll be able to start negotiating a higher salary based on that.
Negotiating with a salary range means you're giving an estimation of what you think you're worth, with a minimum and a maximum salary. Don't underestimate your worth, for you won't have much flexibility to negotiate. Giving the recruiter a salary range shows you're willing to compromise, which is always a good thing for recruiters.
Explain to your potential employer that you calculated your salary based on your skills and the added value you would bring to the company. Don't hesitate to mention your degree, your skill-set, your expertise and your professional achievements. The recruiter will be more willing to negotiate with you.
If the salary you are offered is on the lower range of what you were expecting, don't forget that fringe benefits are also a part of your remuneration (paid leave, luncheon vouchers, bonuses, remote work...). Many young startups are offering a low salary, but they make up with fringe benefits to compensate.
Negotiating does not allow you to be defensive or brutal. Remember that you must always give a good impression to your potential employer: it is advised to show some flexibility during the negotiation, to show that you are a team player.