Learn how to roll. This can increase skills like popping back up and makes you use less energy in the water.
Carry a mission out. This means reverse paddling, side slips and springs. Pick the right partner and they can push you to learn things about your own skill that you might never have known.
Spend time with an experienced kayaker. Learn from someone with more skills and experience and pick up on the lessons that they are trying to teach you. Like anything learning from someone who is better than you is key. They can also teach you about the right equipment and apparel (link apparel to the website) so that you are ready for any challenge.
Become a part of the community. This means going to a conference or symposium and admitting that you want it to become a bigger part of your life. This also falls under the above one, learning from someone better than you.
Try different kayaks. Not all are made the same, as some need different strokes to move a certain way. Some may make you work harder, smarter, or differently.