Don’t put all your eggs in one basket is mine, but then I can’t think of very many…
Oh and no jokey Confucious he say … ones ok? 
My Grandmother taught me this: Cast your bread upon the water and it will come back to you chocolate cake.
You can put your shoes in the oven, but that don’t make them biscuits.
You can’t polish a turd.
Don’t wear your socks in the rain!
-Fonzie’s dad
The Kids in the Hall juxtaposed two that go toghether nicely, especially if one is a reply when somebody else uses the other.
Announcer: Forty Helens agree–Great minds think alike.
Helen: But fools seldom differ.
Let the balls roll where they might…
Man with hand in pocket feel cocky all day.
I don’t really know if I have a “favourite folk saying”, but here are two of dad’s:
“It ain’t what you want, but what you eat that makes you fat.” (i.e., “Be happy for what you get.”)
“Well, it’s pert’ nigh but not plumb.” (i.e., “It’s not perfect, but it’s pretty close.” Best said with a fake Southern accent.)
I’ve heard this one two ways:
“It’s the bit dog that hollers.”
“It’s the hit dog that hollers.”
(I even did an email survey of friends to try to determine which was “correct” with no definitive results. I prefer “bit.”)
It is what it is.
or
Put your wishes in one hand and shit in the other and see which hand gets filled up first.
plnnr, the “wish in one hand” saying is a favorite of my Mom’s.
My great-grandma’s handed down wisdom was this: “Everything in moderation. Including moderation.” In other words, it’s OK to go overboard sometimes, just don’t make a habit of it.
Heh
I like your great-grandma’s wisdom LifeOnWry. You can’t really add anything to that… 
Why would your mom wish for a hand full of crap?
Beans beans the musical fruit the more you eat the more you toot
Two of my Scottish Granny’s wisest:
“Put a beggar on horseback, and he’ll ride you to Hell.”
“There’s nae pockets in a shroud” (that is, “you can’t take it with you”)
And my Canadian Grandfather’s WWI army wisdom (which I’ve quoted before on these boards):
“Keep your mouth shut, bowels open, and never volunteer.”
One I have used here before:
Life is like a shit sandwich… the more bread you have, the less shit you have to eat.
It is easier to get forgiveness than permission.
My Grandad:- “Never go to bed the same day you woke up”
Guess I inherited his body-clock.
My favorite might not exactly count, as it was taken from a Terry Pratchett book:
“The shorter you are, the closer you are to groin height.”
I use it whenever people poke fun at me for being short (I’m 5’3", folks). Another good one is a fave of my mother’s, credited to Mark Twain:
“A lie can get around the world before the truth can get its boots on.”
don’t panic