Saving!

OK, this must be really obvious, but I've googled it to hell and not found a genuine answer... How on earth do you save your progress in Twilight Princess?!

I've played for over three hours, and it's given me two chances to save - once right near the beginning, and then when I first got turned into a wolf. I then played on for an hour or so before quitting for the day. When I loaded the game again I was right back at the start of being a wolf, meaning I had to do the while Hyrule castle / dungeon part again.

There must be some way to manually save without having to play for two hours at a time?!