I do not know if you are referring to "personal brand marketing" or your startup/product marketing, there are different things. One should be done by you, the 2nd should be done by your CEO/business partner.
There are tutorials on marketing, and you can learn from others experiences. For example there are a few tricks of personal development in this video (ignore the title)
I understand your pain, going to meetups and local conferences was a big blind leap for me, but after just a few weeks of feeling strange, lost and weird, it's all working out (my network is growing daily, I learned a ton of stuff about programming and local projects, I've made developer friends of all levels, I'm helping junior devs to learn, I'm learning about technologies I want to learn from experienced users first hand).
The most important thing I learned by going to tech meetups: everyone felt the same as me, lost, confused, scared, now knowing what to do etc. But the desire to "evolve, grow" all led us to that moment.
Maintaining relationships is easy, talk about programming on a chat (skype or whatever), and meet up with ppl once a week or so. It's way easier than the close friends/wife relationships.
It's sort of a time management issue for me. If I spent the same amount of time on networking/marketing that I do on coding, I'm sure I can make some progress. But I can't do both. When I try to do both, I fail on both fronts. So, this post is me coming out and finally saying, I can't do both, and I accept it.
I may be mistaken, but in most cases I have met (including me), in my short "going out" period, doing a small amount of networking (<30% compared to code time) actually help to do bigger leaps in knowledge, opportunities and career overall.
Do not under appreciate the human contact, ppl trust more other ppl that met face 2 face, you can find out answers from stack overflow, but actually talking about the technology and problem it may be better on the long run, with the same experienced person it could reply to you online.
I can't understand how did you failed, we're here on the long run, we're here to stay and learn 10yrs from now too.
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