To Improve your Gaming Skills:
1) Improve Your Critical Thinking Skills.
2) Improve Your Mental Dexterity.
Try different games, choose one you're interested in, and dedicate time to playing that game.
Try playing with pros so that you can learn something new from them.
Master your communication skills and learn to control your emotions to get better communications with your team mates while gaming.
If you want to become a better gamer, make sure you can't blame your losses on faulty gear and the wrong settings.
Learn the nuances of the tools and abilities you've been given so that you can use them in creative ways.