Be confident !
In the past a couple months, I have changed my job twice. Because the company (a small pharmaceutical Co.) that I worked for was shutting down, I had to find a job before being laid off. I just asked for a small rate increase - 2% when I was offered a job. But I didn't like the working environment and company culture. So I started to look for another job. This time when I was offered a job, I was asked what my expectation was. ....... I got the job with a big rate increase - 14%, a total 16% rate increase in two months!