According to this page navigating between highlighted usages:
(source: jetbrains.com)
can be done using F3 or Ctrl+
I've found on mac that Ctrl + G works for this purpose well. It actually selects the occurrence for you, which is fine for me. Shift + Ctrl + G for the previous occurrence.
On Windows/Linus this should be Alt + J and Shift + Alt + J respectively.