A few other comments that were shared outside of here that I want to include in the revision are:
1. Ask their practice or research focus and search for related hashtags
2. Clarify RT as something related to the course (a to also include the course tag)
3. Consider adding a video link or so of usage
4. Bullet the learning intentions for clarity
5. Give an example of the additional accounts to follow things they are interested in but often do not get to read
6. Acknowledge Twitter as a public conversation so taking care is a legitimate concern though not a reason to avoid
7. Mention some literature on this topic such as http://dx.doi.org/10.1016/j.nepr.2015.06.002 and evidence-based recommendations https://www.academia.edu/20798876/Student_Handouts_Towards_Higher_Impact_Blogging_and_Tweeting_in_Connected_Courses