run these commands on the remote host
$ mkdir ~/.ssh
$ chmod 700 ~/.ssh
run these commands on your local computer
$ ssh-copy-id -f sahumada@ssh.texla.cl
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/sahumada/.ssh/id_rsa.pub"
Number of key(s) added: 1
Now try logging into the machine, with: "ssh 'sahumada@texla.cl'"
and check to make sure that only the key(s) you wanted were added.