Ubuntu Servers :: SSH Setup - Login With Key Authorization

I just got unbuntu server edition installed on my server along with openssh-server. Now I am trying to set ssh so I can log in with a key authentication. I am using this guide to do it through putty on my windows machine. [URL]. After I installed ssh I logged in correctly. I then proceed to generate a key in putty. Now my problem starts when i try and put that key onto my server.

The tutorial says to type in
mkdir .ssh

My server says it cannot make that directive because it is already created. So I proceed to the next line. I believe this code sets permissions?
chmod 700 ~/.shh
Nothing happens just goes to a new line

Then I did this
cd .ssh
nano -w authorization_key
then I copied and pasted the key I got from putty gen into this file pressed ctrl o and then ctrl x

When I try logging into my server using the key auth it simply asks for my login, once it is input it says authorization invalid then ask for my password.