Make Your Own Limitations and Stick To Them
This challenge is a bit of a tightrope. The goal is to FIRST sit down and decide on some limitations for yourself. This could be something technique focused like:
• Only ever play two notes at a time
• Play as many open notes as possible at all times
• Only use bar chords
• Write a melody that emphasizes hammer-ons
Or you could go music-theory focused:
• Only use minor chords
• Only use major chords
• Write in a specific mode
• Implement fifths and major sixths into your melody
Or you could go emotion-based:
• Write something sad
• Write something happy, with a sad section
• Write something hopeful
The idea is that you come up with parameters/limitations for yourself FIRST, and THEN you start writing. Again, you don't have to write something difficult - it could be simply a chord progression or a single-note melody. But you must try as hard as you can to fulfill the limitations you've put on yourself.
Have fun! And remember, you're not setting out to create the masterpiece of your life, you're just practicing creating your own music.