In general, wired connections are better than wireless connections, and wireless connections are better than cellular based connections.
Plan ahead for Zoom meetings, and as often as possible, join Zoom calls from locations where you have access to the best Internet connection you can manage.
Mute your microphone when you’re not speaking
While your microphone is on, Zoom is sending an audio stream – even if it consists of no useful audio – to the Zoom servers. Similarly, while everyone else’s microphone is on, you’re downloading their audio to you.
If only the person speaking has their microphone on and everyone else is muted, only the minimum amount of audio data will be sent.
Stop your video when you don’t need it
If you are an instructor or moderator is okay with you doing so, start your video only if you need to share something visually on webcam and stop your video when you don’t need it.
Video data works the same way as audio data described above – turning off video can save a lot of bandwidth.
This does have some impact as you lose other’s visual signals that make communication easier but, is the most effective way to manage Zoom problems on a bandwidth constrained Internet connection
Set up the meeting to support muted audio and turned off video
If you are organizing a Zoom meeting have participants muted and video turned off by default, you can set that up when creating the meeting.
Turn off HD video
If you do decide to go ahead with video, you can change Zoom settings to turn off HD video and save bandwidth both for you uploading to Zoom, and for other participants to download your video stream.
Avoid other Internet activity
Zoom competes with all other applications for your Internet bandwidth. If you experience issues:
try closing out any unneeded applications. This particularly applies to bandwidth extensive applications, such as large file downloads or uploads, streaming video, backups, etc.
Also consider other users on your Home network: if family members are playing online games or streaming video via Hulu, Netflix, or other similar platforms, their Internet traffic will compete with your Zoom call.
Communicate with instructors/moderators
If you know ahead of time that you will be on a slow or otherwise insufficient Internet connection, or discover so during a call, let your instructor or moderator know so that they can adjust if necessary.