Here’s a link to the Coroflot Design Salary Guide, for Product Designer in San Francisco:
That’s a pretty specific set of criteria, and there are only 16 responses there. That graph shows the 25th, 50th and 75th percentile. Since this is your first job you should put yourself all the way to the left side of that graph.
If you back out to look at all of California you get some more detail:
Again, put yourself on the left end of that graph.
Hope that helps!