How can I stop judging myself so bad?

took me till recently to see I was doing that myself all my life. to change though ..... I am filled with negativity and cynicism. so easy to say "don't be!" but it is a challenge to alter the way I think and 'positively' too !

I usually end up thinking of the ending for Monty Python's "The Life of Brian" . "You always got to look on the Bright side of Life" .