@patrascan @butterface I guess that's as good a way to start as any, but personally I hate that trend with a passion. There are (or maybe were?) so many people doing it that it clutters my feed, and the posts are pretty much devoid of content so I get nothing useful out of them, except on the very rare occasion that one of the covers looks interesting.
Of course nobody (except your server admin) gets to tell you what you're allowed or not allowed to post here, so if you want to do it, don't let me stop you! I would just ask that if you do this, please mark the posts with a hashtag ( #20books or #20books20days or whatever people are using) so those like me who don't want to see those posts can filter them out.