To be proud, haughty, or arrogant; to behave conceitedly or boastfully (written 驕る/傲る). Note: this is different from 奢る meaning 'to treat someone (to a meal)'.
成功してから彼はおごってしまい、周囲に反感を買った。
After his success he became arrogant and drew resentment from those around him.
おごると足元をすくわれることがあるから気をつけなさい。
Be careful not to be arrogant; it can lead to downfall.
彼は若い頃からおごるところがあったが、年を重ねて落ち着いた。
He used to be haughty when he was young, but he calmed down with age.