Install org2blog. I put the package in my own emacs configuration folder. Path to org2blog: ~/.spacemacs.d/layers/org2blog/.
org2blog depends on
To better manage the packages, I just put the two packages above right under the same path to my org2blog.
Put following code in your emacs configuration file, e.g. ~/.emacs.d/init.el. Of course, change to your private infomation, including my-blog, url, username. You need to put /xmlrpc.php after your url. That’s for XML-RPC server of your homepage. It only accepts POST request.