Ensure you have joined the permanent test session (Note. this is provided by Zoom and not by UCL) to check over your setup prior to a live class. Try to use the same hardware and location to ensure you can join and take part without any technical problems.
During a session
Join the session 15 minutes before its start time (Note. you might not be able to enter the session if the Host hasn't started it but you can test your audio and video settings);
Check your audio and video settings;
Close down any other unnecessary applications you have running;
Mute yourself/participants when not speaking to eliminate background noise.
After a session
Locate the recording should you wish to review any of the material or discussions.