I saw this image on LinkedIn more than a month ago and it made me smile (along with all of the comments). My days in the corporate leader role were filled with meetings all day every day and it was difficult to get "things done." Besides multi-tasking during meetings, here are my suggestions for making meetings more effective. Please add your ideas in comments!
Be present in meetings and ensure you should be there
Being present means that your attention is there with the meeting
Be prepared
Take notes and participate
Question yourself, should you be there if you are multi-tasking and not really paying attention? What is the purpose of your attendance? If you are not adding value, do you need to be there? What can you do to excuse yourself from the meeting?
EVERYONE's time is valuable - if you or other team members are not adding value or participating, are you wasting time?
Ensure there is an agenda and it is being followed
As a meeting organizer, ensure the meeting has purpose - if you have a recurring meeting and there are no additional updates or status, cancel the meeting.
Assist meeting organizer to stay on track and accomplish purpose of meeting
Make meetings fun and engaging
Start meeting with five minute game, relevant news or story (this will help as inevitably some participants show up late)
Ensure every one has a voice and feels comfortable otherwise valuable information is missed
Value meeting schedule and stick to it
Again, everyone's time is valuable! By sticking to the agenda and staying on track time-wise, the meeting will be productive - if additional time is required, schedule separate meetings for deeper discussions or follow-on meeting
Seems like all of this is common sense but how many meetings do we attend on a daily basis that you feel are just a complete waste of time? Or you know, we can just all do a plank during the meeting like below and that should make them short and productive!

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