Note: You must create a new topic before creating a new post. Just click on "New topic" link the user menu. Of course, you must be logged in to do it.
You can create a new post using "New post" link in the user menu.
1. Click on "New post" link in the user menu on the front page.
2. On the opened page you can just insert a link of the article that you want post and then click on "Go" button or click on "Skip" button and procced creating your own post.
After creating a post you will see your post on the front page. It's done.