Boasting begins where wisdom stops. Japanese Proverb
Don't feel the need to brag about your skills and accomplishments. If anything, you want to keep your prowess as secret as possible, not allowing anyone to know just how much, or how little, skill you have. You are always safer playing your hand without allowing everyone else at the table to know what cards you are holding.
Remember, no matter how skilled you are, there will always be someone out there who is better, younger, in better shape, etc. It is mere folly to go around bragging about your skills. Boasting reveals a lot about a person, none of which is good. Be humble and sincere. Have a purpose in everything that you do. If you must boast about yourself, do so with hidden purpose behind your actions, one that is a part of your strategy. Don't brag in a selfish attempt to impress others.