Write a soapbox story displaying your wares and asking whether anyone wants to follow you. Tell them you need to make the required quota of 100 followers. I did that and gained the required number fairly quickly. As regards submitting to publications, most want drafts rather than self-published content on the platform. The problem is it can take from days to weeks for them to publish stories. Some publications don't even bother replying, so you're left guessing. The publications I've managed to have content accepted on include Writers' Blokke, Everyday Science, Math Simplified, In Fitness and In Health, Gardening, Birding and Outdoor Adventure, Illumination, The Road to Wellness, The Cookbook for All, The Shortform, GetHealthy, Feedium, Synergy, The Haven and Geek Culture.