In this industry, if you quit learning new things, you’re done.
The best engineers never stop learning. That’s why they know so much more than everyone else. Fortunately for you, it’s quite easy and straightforward to keep learning on your own. Unlike the old days where you had to spend tens of thousands of dollars on a college degree and follow it up with expensive courses and seminars, today’s world offers many excellent opportunities to learn new things at low cost.
Read blogs and books. There are many excellent blogs out there. Follow people you consider to be experts, and see what they are reading.
Write your own blog. Nothing increases the rate of learning like having to explain something to an audience.
Study your framework and libraries. Not just the documentation; also closely examine the source code. Great examples of good programming style and techniques can be found there, because this code is reviewed and improved upon by hundreds of people.
Join a user group. Being able to talk to peers helps learning a lot. Give talks occasionally, as this forces you to present your ideas.
Join an open source project. These are great because they often have a list of known bugs, giving you an opportunity to improve the code for thousands of people. Also, help with the documentation. Many open source projects have weak documentation, so this is an easy way to get involved. Finally, add new features to the project.
Listen to podcasts and webcasts. Podcasts are great for the commute. Webcasts provide good examples of actual code, explained in a simple way so the presenter can reach a greater audience.
Study your business domain. For example, if you’re working on financial applications, learn more about the financial aspects of the business.
Learn productivity and management skills. You might not be a manager, but these skills are still awesome to have, and will help you in many ways.
Finally, whenever you can, teach others. Learn, practice, teach. This is the way to mastery.