Not directly MMA related, but an optimistic mindset and enthusiasm will definitely help with the grind of training and pre-fight nerves.

Positive Self Talk

Have a mantra such as “Cool, calm & collected”

Here‘s a list of other possible mantras

Positive Room Entrance

Each time that you walk into a room, pick out 2 things you like and think about why. Make it as random & obscure as possible.

Remember a Happy Memory

You can’t think both positive & negative at the same time. Recall a time that you were really happy to improve your mood.

Smile & Breathe Deeply

Works best if you are anxious in my own experience. Anxiety is a survival response – you wouldn’t smile and breathe deeply if your live was in danger – thus the body provides feedback that all must be well and there’s no need to worry.