Use Twitter, Facebook, LinkedIn, Instagram, follow other researchers, leaders in the field, science & technology institutions and pages, reshare interesting posts
Write a blog, Wordpress, Blogger etc. do it yourself with Hugo, Jekyll or similar. Write about your research, interesting activities, how you solved problems, challenges you face, and of course about your published journal articles. Share these on your social media accounts.
Follow feeds (i.e. RSS) from your favourite journals, science & tech blogs, ideally in a feed app like Inoreader or Feedly. Reshare interesting articles on your social media accounts.
Measure your impact, that means, try to measure or otherwise quantify how many people you reach, what audience you have, how and how often your outreach activities are shared in the networks.
Managing outreach activities like that can become time-consuming. Yet, it is one of the important parts of research (and education) that we are able to effectively communicate (and therefore educate about) what we are doing and why. At the end of the day, most of our research is funded more or less directly through the public, i.e. tax payers. I believe it is really a good way to connect and give back.
Now, to lift these activities to the next level, you could use ("some more") tools.
Self-promotion (e.g. PhD student)/small team:
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https://www.contentcal.io/
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https://hootsuite.com/
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https://buffer.com/
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https://www.kontentino.com/
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https://www.socialchamp.io/
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https://mavsocial.com/
Workgroup/department level:
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https://www.sendible.com/
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https://www.socialpilot.co/
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https://meetedgar.com/
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https://www.agorapulse.com/
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https://sproutsocial.com/
Connect workflows via: Zapier.com
