A wish-granting genie IRL! Nice to have. Thanks!

A video introduction to meshes would be most welcome.
I made my first mesh by adding and modyfying existing points and the picture inflated as a blowfish moving all vertices to four sides of the original bounding box. I made my second mesh using "set" and it was alright, but when I tried to move vertices (still in edit mesh mode) the results were ugly. Quite accidentally

when I already thought I'm through with meshes

I started to move vertices outside of edit mesh, in standard setup mode. And it's beautiful, but the trial and error process was rather hard. So please

make a video.