Writing posts using markdown is an easy task. But why don’t make the whole process easier? Emacs users would thank for the markdown-mode existence.

After downloading and loading the markdown-mode.el in Emacs you just need configure the latter to autoload the markdown-mode when you open your markdown files (e.g. .md and .markdown).

(autoload 'markdown-mode "markdown-mode"
   "Major mode for editing Markdown files" t)
(add-to-list 'auto-mode-alist '("\\.markdown\\'" . markdown-mode))
(add-to-list 'auto-mode-alist '("\\.md\\'" . markdown-mode))

For usage see Emacs Markdown Mode.