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
Without labor, you can not even catch a fish in the pond.
The forbidden fruit is sweet.
What goes around comes around.
Get your sleigh ready in summer and your (horse-drawn) cart in winter.
Better to see once than hear a hundred times.
When I eat I am deaf and mute.
Crowded, but not aggrieved.
Live for a century, learn for a century, but die being a fool anyway.