I "think rather HIGHLY of myself".

…
"If my 'superpower' were ARROGANCE, my superhero-name would be

'Dr. Aro-GAHTO'."
(--Dr. Sheldon Cooper, 'The Big Bang Theory')

There's a DIFFERENCE between

MY BLATANT, JUSTIFIABLE, OVERT, SUPPORTED SELF-CONFIDENCE

and

RUDE, UNASHAMED, QUESTIONABLE COCKINESS!


((… FIRST, display "CONCRETE" REASON(S) for your CONFIDENCE.
THEN, continue to "produce" even MORE EVIDENCE of your "STRONG" SELF-BELIEF.
FINALLY, bask in the JOY of ACCOMPLISHMENT!))


...