A few suggestions:
Add it to alternativeto.net , reportedly it is one of liberapay top referrers. It is also one of the top referrers of join-mastodon. You can see the referring websites using similarweb.
Mention attractive features or qualities of the project, on the website/readme pages or on alternativeto reviews.
Similarly in the release notes of a release try to add a section called "highlights" with especially attractive improvements, some users will probably not go over a long list of changes.
add topics to the github or codeberg or whatever repository .
Link to review platforms (like alternativeto or google play) from your website and ask for good reviews and likes.
Post to reddit or hacker news or lemmy, don't do it too frequently and the posts should have significant value, once a year seems like a pretty safe bet. saying you are the author and answering questions is also good.
Use star track to measure the success of your promotion efforts and see what works in practice. Consider developing other metrics like website page hits or measuring number of active users like shown on the-federation.
further reading:
The (Detailed & Creative) Playbook for Getting More GitHub Stars