Add #t=(desired_minute)m(desired_seconds) to the end of the URL. For example for this video the resulting URL will [https://www.youtube.com/watch?v=2MtOpB5LlUA#t=3m44](https://www.youtube.com/watch?v=2MtOpB5LlUA#t=3m44) to link to the part of the video I want people to see