The nature of arrogance

To believe oneself to be above average intelligence is not arrogance.
To believe oneself to be handsome is not arrogance.
To believe yourself to be the richest person in the world, if there is strong evidence, is not arrogance.

Arrogance is rejecting the truth.

If someone advises you properly about your flaws, but you refuse to listen simply because the advisor is seemingly poorer or less intelligent than you, this is arrogance.

Thinking you are definitely a better Muslim than another Muslim is arrogance. Because Allah states we do not know a person's true ranking with Him, so to proclaim otherwise is rejecting the truth.

Believing you can get away with sinning without repenting is arrogance. Common sense says otherwise, Allah states no one is guaranteed safety from the Fire, so why would you reject this truth?

To conclude, believe in yourself and your strengths - this is self-awareness. But never delude yourself into thinking you are above the truth, for this is true arrogance.