Couple ways you could do it: 1. a webcam recording of yourself, using quicktime (only on mac) or similar webcam recording tool 2. a screen recording where you talk through a slide deck of news, roadmap, etc. Again, using quicktime or chrome extensions such as the one I built: https://outklip.com. Outklip's advantage is you can record webcam along with screen, annotate during recording, do post-editing and upload to YouTube with a click.
I interiewed Sid Sijbrandij, the GitLab CEO (GitLab has 500+ members and is all remote) on running a distributed company. He said this about alignment: "I think it’s really important to write things down. People are very efficient at reading things. So, if you wrote it down you can refer to it, so you don’t have to say everything again, you can just drop a link. So, we write down a lot, in our handbook, on our OKRs page, you’ll find all our goals and strategy, etc. And at some point you keep repeating that, keep dropping those links and you keep answering questions. So, repetition is still needed, repetition is easier if you have one writeup and most people have already found it even during onboarding.". Interview video and notes here: https://outklip.com/blog/gitlab-building-a-distributed-compa...
Another interview with Sid about how GitLab uses video for remote work: https://outklip.com/blog/using-video-for-remote-work/.