The Host of the meeting should do the following:

1. Click on Manage Participants in the meeting controls at the bottom of the Zoom window.
2. Hover over the name of the participant who is going to be a co-host, and choose More.
3. Click Make Co-Host.

The user will then have access to the Co-Host controls. 

See below for related FAQ articles:

Zoom FAQ's
New to ACM? How to access your Zoom account
Zoom - How do I log in?
Zoom - I missed a Zoom lesson, how do I catch up?
Zoom - What are the system requirements?
Zoom - Noise issues (echo)
Zoom - Internet speed
Any issues, please contact the Digital Education department. You can reach us here: