This may be controversial – I’ve learnt that we cannot ask ourselves (or other folks) to “be humble” or, for that matter, to be grateful or to take things less seriously.
The notion that we can tell ourselves – “Hey, I know you think you are wonderful. But, it isn’t right to let people know you think that way. So, tone it down a bit so it looks more acceptable, will you?” – is flawed and comes across as fake.
All we can do is to help ourselves gain perspective and understand reality. And, when we do realize how little we actually know and that most of what is working in our life is a result of accumulated privilege and luck (my theory below), humility, gratitude, and a sense of humor flows easily.
Like many of life’s best things, humility is simply a by-product of a good product (perspective). The same holds true for gratitude and keeping a sense of humor.
(H/T: Kapil Gupta for an excellent articulation of the “be humble” problem/charade)