This achievement can be easily unlocked in the tutorial world but note that the layout of the tutorial world sometimes changes but the method to unlocking is still the same.Load up the tutorial and complete the basic features so you can go through the opening in the wall.
Once you have gone through the wall you're in a town and on the left there will be an area where there is farming and animals with pens.
You should see some pens with chickens, cows, pigs and you guessed it ocelots which are on your right, in front of the ocelots is a chest that contains the raw fish you need. Grab the raw fish and equip it and crouch (Click
) and open the pen so that the ocelot runs out, follow it but not too close so you don't lose it, then you'll need to wait for the ocelot to calm down and stop being scared.
When it calms down it should come back to you slowly with its head down looking at you, once near press
to tame it and providing it worked there will be a flash of hearts and the ocelot with turn into a either a ginger black and white or Siamese cat.
Note: If the ocelot gets too close it will get scared off again and you'll have to start over and wait for it to come near you again. As well as this it you tame in this scared mode you will still see a flourish of hearts but no taming will occur.Here's a video (Ocelot location may be different but the method is the same)