There's a lot of good information in this thread, but I can add this: join a SA ...

There's a lot of good information in this thread, but I can add this: join a SA organization and/or special interest group:

   Usenix, https://www.usenix.org/

   LOPSA, https://www.lopsa.org/

Then read the journals, even the articles that don't interest you now, and follow the email lists.

I'd like to add that LOPSA also has a mentorship program, free for all members.