If you want to get pedantic about a joke, I didn’t recommend eating dog poop. I was commenting on what passed the filter of that pithy aphorism, and what didn’t.
Don’t eat the fire truck.
Don’t play that creep’s game - (this is a paraphrase of a line from Dirty Harry)
Don’t fuck with the (name of dangerous animal here)!
That’s his/her problem.
It’s pointless and time consuming to throw a rock at every dog that barks at you.
Nobody gets out alive.
Apropos of the last week in Houston (even though it really has nothing to do with flooding), an early mentor of mine trying to explain how I needed to let some things go and only worry about the important stuff.
“Be like a little duck. If it rains you swim. If it don’t you walk.”
From my Dad, on the subject of surviving West Point and/or war:
Never miss a chance to take a piss, take a nap, or keep your mouth shut.
From an old boss:
The secret to life is knowing what to do next; the secret to happiness is doing it.
Deadly Nightshade is pronounceable, organic, AND non-GMO!
And if you eat it, you are shit-out-of-luck, unless you can pronounce physostigmine.
Never shit higher than your arsehole (with regard to finances).
If it’s going to be, it’s up to me.
“You can’t care about other peoples’ problems more than they care about their own.” - somewhere on the internet.
My own is: better to have it and not need it, than to need it and not have it. That is why we’re insured to the hilt on everything and take way too much money on vacations.
“Other people can see how you’re acting.” - My Mom.
She may have been worried about potential embarrassment, but it’s also something to remember when you’re on your own.
Pithy advice to her doctor, from my 98 year old mother: “I’m not sick – I’m old.”
“It ain’t your emergency.”
Advice given to me by an older EMT when I first starting driving ambulances. He was telling me to limit my own risk when attempting rescue. I’ve expanded that in a way, to remind myself that in life:
-There are a lot of problems that not only can’t fixed by me, they can’t be fixed by anyone.
-If I “hurt” myself (bankruptcy, exhaustion, etc.) trying to help, I’ve done more harm than good.
-My first duty is to my family & myself, and there is no guilt in walking away.
and the final maxim…
-I have no obligation to treat self-inflicted wounds.
Don’t pith on the electric fenth.
Satchel Paige said “How old would you be if you didn’t know how old you were?”
I’m 25 and sticking to it.
Reminds me of one I got from a restaurant placemat, of all places:
“Character is how you act when nobody’s looking.”
I got this one from a roll of paper towels
“Only make promises you can keep. Keep the promises you make.”
Measure twice cut once. It qualifies as one of the best yet least followed pieces of advice my dad would give me
“Don’t let you mouth write checks that your ass can’t cash”
“Your lack of planning does not constitute an emergency on my part”
Perhaps the best: “No good deed goes unpunished”
P.S.
In respect to un-necessary advice or help: “Hey, I’m fuckin’ this monkey, you’re just holdin’ the tail” 
If you don’t get told “no” every once in a while, you aren’t asking for enough.
In the workforce: Poor planning on your part does not constitute an emergency on my part.