No, you don’t throw your students into the blogging pond and hope they swim. Much better to provide a pier for them to look out on, and dip their toes into. Then they can either dive in or gradually submerge themselves. This post is about dipping their toes in.
And one of the best resources I have found about student blogging is Sue Waters. She has lead seminars in blogging for participants, as part of the excellent ETMOOC (still running, best MOOC I have ever participated in). Scroll down in the post to the section Scaffold vs Struggle. You can see a clear progression that allows students to dip their toes in with comments, get comments on their comments, and gradually work toward posts themselves. Scaffold.
I consider blogging the new essay writing, and think it should be taught in a language learning context. Yes, teach how to make a link, and how to add a picture with a caption, and how to make the picture link to another page. More important, teach how often and where and when to make the links, from which anchors and to what targets. There is a book, or at least a guide out there, waiting to be made. Blog writing for the non-native speaker.