Shout out on Twitter that you want to mentor and ask for retweets. Alternatively, get in touch with a person that is already mentoring students as they generally know more people that are interested.
Get to know each other during introduction call. You can talk about what the student knows, and what goals they have that you can help them with.
Every person is different and we all need different kinds of mentoring depending on where we are standing.
Together with the student you can start to thing about what makes most sense.
Some examples are:
- weekly mentoring calls (long term)
- help with a specific project (short term)
- ad-hoc help, be the person the student can go to with instant and ad-hoc questions and blockers
- code reviews