With accent marks:
На Бо́га наде́йся, а сам не плоша́й.
Put your trust in God, but don't make mistakes yourself
This Russian proverb is a close equivalent of the English expression "God help those who help themselves".
"Не плошай" means "do not make mistakes", it is an obsolete word and can only be seen in proverbs or books.
Other Russian proverbs
Live for a century, learn for a century, but die being a fool anyway.
(lit.) Whoever gets up early, God gives him
Silent means consent.
Make a fool pray to God - he will break his forehead.
There is no smoke without fire.
Don't go to the woods if afraid of wolves.
~ Seven babysitters make the kid to lose an eye.
The best is the enemy of the good.