I'm just adding...
If you choose to jumpseat with Hawaiian, the minimum time to list for the jumpseat (or nonrev in general) for an overseas flight is 45 min prior. For an interisland flight, it is 30 min prior. If you are at a US Mainland station, list at the front counter. If you are leaving HNL (transpac or interisland), list at the service desk either inside or outside of security. Just be advised sometimes agents will run out of jumpseat forms at the service desk located inside security. In this case, they will make you go out of security to the front service desk to list there.
Also, I've brought this issue up before, but I just want to throw it out there again: attempting to jumpseat in shorts and and a t-shirt - just don't do it. You'd be surprised to hear how many that actually do. It should go without saying, but lots of off-line guys jumpseating on HA are apparently on vacation-mode.
It is true Hawaiian is a laid-back company and great crews, but we have some captains that are still very old school and will not hesitate to deny someone for inappropriate attire. Business casual or uniform works great (no jeans or cargo pants).
Have fun!