Back in the day, jobs were for life.  You put in your 30-40 years and got a pension.  Maybe even a gold watch.  That was then.

Of course, there’s no such thing as guaranteed employment anymore.  But there is such a thing as guaranteed employability.

It comes about by putting into practice the second of my 11 core principles for simple, meaningful success: Earn Diligently.

Learn to Earn

In most jobs, if we’re standing still with our skill set, we’re quickly falling behind. Things are just advancing too quickly – technology, cultural trends, ideas.  A key to keeping up is continuous learning.

Many employers offer some form of tuition reimbursement, and yet a tiny fraction of eligible employees typically take advantage of that benefit.  If your employer will foot the bill for more education, don’t leave that money on the table.  The skills you learn may lead to advancement opportunities, and they will very likely help you land a new job if necessary.

Even if your employer won’t cover the cost of school, there are no- and low-cost ways to keep your skills sharp, like the software training available from Lynda.comand the lectures on iTunes U.  Of course, you can check out the latest books in your field from the library, follow industry blogs, listen to audio books and podcasts, and more.

One of the best forms of professional development is being mentored.  I’ve been blessed to have some great mentors during my days in corporate America (Thanks, Carl!) and in my current work (Thanks, Dick!).

To find a mentor, seek out someone in your field who’s more experienced and/or successful than you are and ask if you could connect on some type of regular basis.  Very often, successful people enjoy coming alongside someone who’s at an earlier phase of their career.

When you approach a prospective mentor, though, make sure you’re ready to explain why you’re reaching out to them and what you hope to learn.

Be Great at Being Yourself

If two people have the exact same professional skill set and experience, what’s left to set one apart from the other?  Interpersonal skills.

Communication skills (especially asking good questions and listening), relationship building, time management, project management, and the various facets of Emotional Intelligencecan help keep you in demand.  All of these skills can be honed through the no- and low-cost options mentioned earlier.

Other personal habits matter to your career as well – from groomingto your use of social media. Staying physically fit can also make a big difference.  Doing so gives you energy and communicates a lot about your discipline, life balance, and self-respect.

Cast a Wide Net

By some estimates, 80 percent of available jobs are not posted.  They get filled through referrals.  If you find yourself between jobs, having a great network is essential.

Of course, LinkedInis today’s networking platform of choice.  When you connect with someone – a co-worker, former co-worker, former classmate, friend from church – you gain potential access to their network.  At very least, you could ask your connection for an introduction to someone in their network.