To improve your altmetrics scores you need to create an online presence and share information about your work and your research outputs online.
There are many ways to do this such as:
Blog about your articles or work and ask others to write blog posts about your work.
Become active on Twitter and tweet links to your articles and other work. (If you don't want to join Twitter, ask colleagues if they would be willing to tweet on your behalf.)
Use social networks for researchers
Register for researcher/ author IDs
Register for IDs such as an ORCID id, and keep your list of publications up-to-date.
Make all your research outputs available online
Make all your research outputs including data, code, videos and presentations available online by using on content hosting tools such as: