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
(lit.) Whoever gets up early, God gives him
Make a fool pray to God - he will break his forehead.
Оne sees the mote in another's eye and ignores the log in his own.
Live for a century, learn for a century, but die being a fool anyway.
The quieter you go, the further you'll get.
One head is good, but two ones are better.
If you like sledding, you should like to carry the sled.
The demon is not as scary as he is depicted.