Haha, okay. Well, it's very easy.
There are tons of online tutorials on the actual publishing part, the trickier part is the advertising, growing your reader base (assuming you want to write multiple, not just a one-off), etc. There are some good books and podcasts around that though, but it does take quite a while to learn. Plus a lot of times it involves blogging, which is extra work, but one of the better ways to monetize it.
The publishing part is super easy though.
What exactly are you looking to do? Make lots of money? Become a writer full time? Publish a single story you've had kicking around? What genre are you thinking?