video promotion tips

There's a bunch of platforms and social media sites to promote videos, but what do you guys find the most effective? I'm just curious so I can focus a little bit more attention to learning specific and effective platforms rather than just posting a bunch promotion haphazardly.

Hello everyone, Wanted to know your experiences of using Reddit, only used it a couple of times and seems like a lot of trolls on there. Let me know what you think of it please.