This is a great thing to be thinking about! Some things to consider:
- Many employers will have some kind of training budget available, or some resources that you can use. For example, at my company today there's a large book collection, all employees can take free online courses at Udemy, and if there is a technical conference or training session I'm interested in, I can apply for it. This is a great thing to find out about as soon as you start a new job. While you can learn on your own time, getting paid to do paid-for learning is even better!
- Set aside personal time for skill development. It's an investment in your career. Be deliberate about what you're trying to learn and how you're going to try and learn it. I've been successful with setting a standard time (an evening a week, or an early start to my day a few days a week) to work on career-growth projects.
- Keep up to date with what's going on in the industry. I use a free Feedly account to subscribe to lots of tech websites, which is a good way to keep awareness of the kinds of things people are talking about. I also subscribe to development podcasts and listen to them while I'm commuting or doing chores around the house.
- Find people who have skills you're interested in at your company and pick their brains. You might even find a mentor.
- Teach people new skills you're learning. You can give tech talks at work, or propose talks at local meetups, or mentor other people. Having a deadline to have to actually teach people something is one of the best ways to force you to really, really understand it.
- Check out the amazing quantity of free technical content on YouTube. Most of the major tech conferences publish their videos for free now, often the same day. I have a list of conferences I would love to attend if I had time and budget, and then make myself a playlist of the talks that look interesting to me, and then watch them at double speed. It's crazy how quickly you can absorb information in that format, even if you're beat at the end of the day.
- Finally, it's also ok to relax. The bleeding edge of tech industry moves fast, but most companies don't build things right at the bleeding edge. Most of the skills you develop will both be valuable for many years. Even if not, having learned them makes it far easier to learn the next skill. It's much harder to learn the first programming language than the second one. A lot of skills (how to test, how to document, how to build reliable software, and so on) are almost entirely portable from language to language. It's as important to have real, deep skills in an area, even if it's not in the bleeding edge, than it is to be aware of the latest and greatest. It's actually a bit of an interview red flag if people are only talking about the "buzzworthy" stuff.
Good luck! The fact that you're thinking about this already is a great sign.