Finding a penny heads up is GOOD LUCK and you must pick it up, but a finding a penny tails up is bad luck...so you leave it where it lay.
I once left a tails up penny on my doorstep for several months in a row. Thankfully someone finally removed it or it would have stayed there forever.
** Which superstitions did you grow up with? And do you still abide by them today? **
"If a man knows not what harbor he seeks, no light will guide him."