Half an hour is not very long.
Why not set aside 30 minutes each day to develop a skill, such as reading books, learning a foreign language, learning about website design, etc.
You only need to spend 30 minutes a day improving one of those skills; over a year, that equals the time of 16 full courses or more than 25 books read.
Starting a habit is much easier than you think. Begin with small steps, then gradually increase the intensity. Leave us a comment and let us know whether you find it difficult to develop a new skill or create a habit!