A couple of weeks ago, I started a Positivity diary where I note down each day three positive things that has happened during the day and then gave a overall feeling of the day so Good, Neutral or Bad. I could write down the negative things but I know if I did that there would be more negatives than positives
and I would just focus more on the negatives.
Also, at the back of the diary I left some pages for people to make positive comments. Firstly, I wrote a paragraph myself, tell myself that I was doing good and lots of people were supporting me. Then during the week, I asked my teachers to sign my diary with a happy or funny comment about me and I don't read the actual comment until the end of the day.
So take the other day for example, I've had a really bad day but at the end of it, I read my citizenship teacher comment and it really cheered me up and made me smile.
It actually does work. I would recommend this to anyone who self-doubts themselves or has trouble with negativism.