I don't think advertising the entire blog makes sense, but instead posting links to specific posts in the appropriate lemmy/reddit/facebook/mastodon community/group ao people get something out of it and then subscribe for more.

Since it's a personal blog, I would stick with personal social media. Facebook, Snapchat, X, places where people are following YOU, and would be more interested in hearing more about you.

If it's going to have a consistent theme, you could post something in related communities if they allow it.

This Discord server if you don't mind doing it on Discord.

It has a section for promotions where everyone will see the advertisement you wish to put there.

Depends on the content, but I posted something from my blog on Hacker News and got a good reception.

Write good content, discuss it on relative boards and people will come.

I think we should bring back web rings, but nobody else seems to miss them.

Edit: I'm so old, I should probably link to what a web ring is: https://en.m.wikipedia.org/wiki/Webring

How about reply with a link here? I'm just curious now