Why do I get a lot of saliva or moisture in my ocarina?

The air you exhale contains a lot of water vapour and, in many wind instruments, this condenses when the instrument is cold. This generally isn't a problem with ceramic ocarinas as they are made from earthenware, which is porous and absorbs this moisture as you play. That being said, it can be a problem with plastic ocarinas.

If you are having problems with moisture with a ceramic ocarina, it is more probable that you are getting saliva into the windway. This generally happens for two main reasons, looking down while playing and putting too much of the mouthpiece in your mouth.

Keep the ocarina parallel to the ground. This lets saliva pool in the bottom of the mouth instead of getting into the windway. Get into the habit of regularly swallowing the saliva. Holding the ocarina like this also makes it easier to play as ocarinas are designed to balance between the right thumb and pinky. If you are looking down to see sheet music, get an eye level music stand.

Putting too much of the mouthpiece in your mouth can also allow it to pick up saliva. The mouthpiece should gently touch the outside surface of the lips and should be nowhere near the teeth. If you are able to bite the mouthpiece or it otherwise touches your teeth, you have way too much of the mouthpiece in your mouth. See 'Blowing an ocarina correctly'.