Meditation is the best advice I can give. It does take time and dedication, but it can very much work. Mindfulness meditation can be excellent for mood control, as it teaches the practitioner, in some aspects, to observe thoughts and emotions rather than becoming attached to them.
Mindfulness methods have partly helped me to keep my temper and depression under control. I am still working on it, but I am seeing progress.
Part of the teaching includes that you are not your thoughts or your moods. They exist, and you may experience them, but they are not you. It is why, when practicing mindfulness meditation, it is sometimes suggested not to get involved with thoughts which will inevitably pass through your mind. Observe the thought; acknowledge it. The same goes for emotions and even some situations and events: They happen, but you don't have to be involved with them.