I just watched a video recently, it says:
无论自己发生什么事，都要对自己说:这是正常的
不要问：为什么我那么倒霉？
I think this applies a lot in our lives too. My cousin, Jovial, always asks us to be grateful with what we have, because your inner self will reflect your outer self and therefore your life. Instead of using negative phrases like, “I won’t”, “I can’t”, “I’ll try my best”, it’ll be more encouraging to say "I will", "I shall",and " I'll do my best". The positivity in these latter sentences give you more strength.
The last thing she says is to tell yourself that you’re good for 3 times a day.It makes you feel good about yourself, besides boosting up your confidence level.
“我很好，我很好，我很好.”
“我很勇敢，我很勇敢，我很勇敢.”
“我可以做到，我可以做到，我可以做到."
Does it really help? Let me experiment this and I’ll come back to you after a month.