[phaemon]

You click the "submit" link at the top of the page. Then enter the URL you want to submit. It will then appear in the list you can see under the "new" link.

If people find it interesting, they can then upvote it by clicking the little up arrow beside the submitted link. If enough people do that, then it will end up on the front page. And that's all there is to it!

[nashashmi]

That was quite courteous way to perceive the question and respond. I can do one better:

The link is to a Wikipedia page with a long url. You can submit a title to mask the link. The op posted ".SU" and so .su isn't a link, it's just a title.

[dang]

There's also the second-chance process: https://news.ycombinator.com/item?id=11662380.