Check out markdown, which is basically structured text used for converting into HTML etc. If nothing else, it's a good start for what you're trying to do. 'Sunburst' and 'Cobalt' are nice themes for markdown.
If you edit the syntax highlight files you'll be able to set your own custom formats, codes etc.
how exactly do i create highlighting of such?
Editing the ".tmtheme files", and the ".tmlanguage" files which are what determines/controls syntax highlighting.
I'm pretty crap at it myself, but there's a few tutes around on the forum, and lots more info out there.
Here's some example markdown to get started and see if that's what you're after. Either save it as a *.md file, or just set the syntax to markdown.
# Header 1 #
* * *
- - - -
This is text with a footnote.^1]
An [example](http://url.com/ "Title")
_italic one_ not italic _italic two_