Here is an simple example: "I ran 10km today while you sat on a couch walloping the entire bag of kettle-chips when you should have been doing kettle-bells. Chips are not bells. I ran while you snoozed, therefore I am superior to you."
The ego is inherent in every human being, and whilst the ego itself is innately not a bad thing, one should learn that falling into the ego trap, where you mistakenly think that you are better than someone because of something you have or have not done or possess, is a sure way to allowing Kali, the Goddess of Destruction, a field day pass of fun and games into your personal relationships.
After all, Fat Bob the Builder whose couch territory you have just invaded there, does not even want to hear how General Maximus Aurelius, Commander of the Armies of the North is superior to him (something that might actually be a fact...), much less Tan Ah Kow who in the past 6 months, has only just slogged out one 10km run on a threadmill in an air-conditioned atmosphere, and then openly or indirectly hinted that he's a better man...
So how can one manage his ego better? My thoughts revolve around being more aware of your surroundings and social environment, and to focus on developing yourself as a better person in every way on a daily basis, instead of being competitive and bench-marking yourself against your peers or environment - i.e. in other words, adopt a growth mindset instead of a fixed mindset (social psych buzzword of the last couple of months), which though it does make a lot of sense, is something that is extremely hard to adopt and make a solid habit out of.
Every day a better man, in every way. I think that itself is a hard enough target, but certainly a worthy one to strive towards.