What are your deliberate practices in relation with your work as a software developer / professional, or as a CS student?

Deliberate practice are exercise and repetitions targeted specifically at an individual's weak points and meant to consistently stretch / grow someone's ability. It was described in this Anders Ericsson paper.

To qualify as a deliberate practice, the exercise must satisfy the following:

1. Is not inherently enjoyable.
2. Is not play or paid practice.
3. Is relevant to the skill being developed.
4. Is not simply watching the skill being performed.
5. Requires effort and attention from the learner.
6. Often involves activities selected by a coach or teacher to facilitate learning.

Please answer with one practice per answer. I'll seed the question with one possible answer.