With accent marks:
Глаза́ боя́тся, а ру́ки де́лают.
The eyes are scared, but the hands are doing.
The task can be daunting in the beginning, but as soon as you start doing it, everything becomes clearer and easier.
Other Russian proverbs
The apple never falls far from the tree.
Start taking care of the dress while it's new, and of your honor while you are young.
The quieter you go, the further you'll get.
Eggs don't teach the chicken.
Appetite comes with eating.
Without labor, you can not even catch a fish in the pond.