With accent marks:
Видна́ пти́ца по полёту.
A bird is visible by its flight.
You can say anything about yourself, but only your actions will show your true value. A person is judged not by his words, but by his deeds.
The closest English equivalent is "A bird may be known by its song".
Other Russian proverbs
Another's soul is darkness.
The eyes are scared, but the hands are doing.
Silent means consent.
Measure seven times, cut one.
Beast runs towards the hunter.
If you are chasing two hares at once, you won’t catch a single one.
Be patient, Cossack - you will become an ataman!
Strike the iron while it's hot.