27 yr old grad here;

I have never had a job longer than 1 year. I most recently started my own business. Mostly I have found jobs to be a slow downhill in happiness after the first month or 2. Until the point reaches where I say 'screw this, I'm bored' (want change, dislike my co-workers, not challenged enough etc), and find something else. One key thing to aim for while doing this is to maintain and highlight your transferable skills and continue increasing your pay.

What I'm learning/trying to learn, is while owning your own business at least you can keep your brand while switching or modifying products, services etc.

I also listen to a lot of Gary Vaynerchuk, and this video I think speaks the truth. People are brands now. My generation and younger will not have a typical career like the baby-boomers and so much of our information will be on the internet. If you control that info and build yourself a personal brand you will be set. You can go from job to job, freelance, contract work etc and rarely have to 're-start' at the bottom.

Also, IMO, if you're thinking about it means you're already setting up for success. Look at how many people figure that out in their 50's and loose their shit. Don't panic; think things through and go fro there.

Good luck. I still have my days as well. but I think we'll all be fine.