There are a couple prereqs. You need to have a crypto image (look for k9 in the image name), you need to have an RSA key:
switch(config)#crypto key generate rsa modulus 1024
That should be it. From there, you can do:
line vty 0 15
transport input ssh,telnet
Which effectively enables ssh. Keep in mind that without a crypto image, you can’t generate the key. Without a key, you can use SSH.