Just deep dive into the technology of your choice. Write clearly and comprehensively about your projects, the roadblocks you faced, and how you overcame them.

Another recommendation is to blog on a collaborative project. Could be with just one other person. That way you're reaching a wider social network.

What's very satisfying is googling on some technical problem and finding in the top search results my own blog article from several years back.

Blog early; blog often.