As a Usui Reiki Master and teacher I teach every student from Level 1 on to practice self Reiki every single day. It literally takes about 20 minutes and is crucial to your personal Reiki development and it keeps you balanced and healthy. Somehow I even forget to do self-practice sometimes.
So I found a good interval timer application for my Blackberry and now I set the timer to chime every 2 minutes as I do my practice, changing my hand position on each chime. It helps me to stay present and not worry about time, and my daily Reiki practice is much easier to handle!