Have a good time, all the time. That’s my philosophy, Marty.
I’d leave it where it is, then get it when I needed it. (Honestly, I’ve had to answer that question a lot)
My motto? From everything, something.
I like to think that from every experience I have, I take a little something away that I’ve learned or gained. Even if it’s just learning a short-cut to school, or learning that I’m allergic to something… From everything, something.
(Granted, there’s still one big knot in my life that, six years later, I’m puzzling over what I walked away with, but that’s the exception, not the rule.)
“It just goes to show ya…it’s always something, if it’s not one thing, it’s another!” – I find myself saying this alot.
(upon edit, I see I’ve kind of twisted ArrMatey!'s philosophy! I find myself channeling Roseann RosannaDanna from SNL when I say this)
Also:
“No battle plan survives contact with the enemy”
“You might as well be a mench.”
Really? I find the opposite to be true usually. Or, have I been whooshed?
But, being the good guy I am, I wanna be a mensch! 
I have two, one lofty, one practical:
Fiat justitia, ruat caelum – Let there be justice, though the heavens fall.
DWYSYWD – Do what you say you will do.
“In this life, you don’t get what you deserve. You get what you negotiate.”
“Nothing is won without sacrifice.” I found this is a book by Leslie Charteris, and in context it is very powerful. I try to remember it daily.
I swear, the philosophical and intellectual depth of the members of Spinal Tap is severly underappreciated.
I’ll add my sig.
I have two, depending on the situation. The first, a general, all-purpose motto, is summed up by my signature. The second, used in times of severe stress (almost always caused by the demands of self-centered oafs) is “Illegitimati non carborundum.”
Audere est Facere - To Dare is to Do
Nah, actually, “Never Moon a Werewolf”.
“If you can’t be a good example, then you’ll just have to serve as a horrible warning.”
“The early bird gets the worm, but what of the early worm?” - The way I learned Si_Blakely’s “second mouse” motto.
“Seven times down, eight times up.” - From the inside of a cycling jersey, attributed to a Samurai saying.
“Do the next thing.” - It’s amazing how many times that’s gotten me through a seemingly overwhelming task. Just take the next step. Write the next page, make the next call, set up the next workstation, run the next mile, endure the next hour.
“Every punch, bad intentions.”
“Specialization is for insects”.
And my every day one: “Fuck it, drive on”.
Sic gorgiamus allos subjectatos nunc. - We gladly feast on those who would subdue us.
OK, I stole that from The Addams Family.
I always liked:
We the unwilling
Led by the unknowing
Are doing the impossible
For the ungrateful.
We have done so much for so long with so little
We are now qualified to do anything with nothing forever.
Anybody can be good in a crisis. It’s everyday life that kills you.
My sig line.
(No, not the part about the '99ers…)