I am currently reading "The Champion's Mind - How Great Athletes Think, Train and Thrive" by Jim Afremow, PhD. In his book in the second chapter he defines the mental skills as:
GOAL SETTING - Think It, Then Ink It
MENTAL IMAGERY - Visualize to Actualize
SELF TALK - Feed the Good Wolf
CONFIDENCE - Flex Your Confidence Muscle
FOCUS - A Champion Is a Now-ist
BREATH CONTROL - Breathe Life into Your Performance
MENTAL TOUGHNESS - Build Your Inner Strength Bank Account
ANXIETY MANAGEMENT - Go From Panicky to Pumped
ENJOYMENT - Humour Is the Best Sports Medicine
BODY LANGUAGE - Make a Golden Impression
INTENSITY - Own Your Zone
PERSONAL AFFIRMATION WORK - Power Phrases for Becoming a Champion
I feel all of these are truly necessary for success and we all have many ways to practice these each and every moment. I highly recommend you pick up this book and add it to your library.