“Dance as though no one's watching
Sing as though no one's listening
Love as though you've never been hurt
Work as though you don't need the money.
Live as though it's heaven on earth”

Source: Come to Me

The Autocrat of the Breakfast Table (1858)
Context: Though fortune scowl, though prudence interfere,
One thing is certain: Love will triumph here!
Lords of creation, whom your ladies rule,—
The world's great masters, when you 're out of school,—
Learn the brief moral of our evening's play
Man has his will,—but woman has her way!

As quoted in Journal of France and Germany (1942–1944) by Gilbert Fowler White, in excerpt published in Living with Nature's Extremes: The Life of Gilbert Fowler White (2006) by Robert E. Hinshaw, p. 62. From the context http://books.google.com/books?id=_2qfZRp9SeEC&lpg=PP1&pg=PA62#v=onepage&q&f=false it seems that White did not specify whether he had heard Einstein himself say this or whether he was repeating a quote that had been passed along by someone else, so without a primary source the validity of this quote should be considered questionable.
Some have argued that elsewhere Einstein defined a "miracle" as a type of event he did not believe was possible—Einstein on Religion by Max Jammer (1999) quotes on p. 89 from a 1931 conversation Einstein had with David Reichinstein, where Reichinstein brought up philosopher Arthur Liebert's argument that the indeterminism of quantum mechanics might allow for the possibility of miracles, and Einstein replied that Liebert's argument dealt "with a domain in which lawful rationality [determinism] does not exist. A 'miracle,' however, is an exception from lawfulness; hence, there where lawfulness does not exist, also its exception, i.e., a miracle, cannot exist." ("Dort, wo eine Gesetzmässigkeit nicht vorhanden ist, kann auch ihre Ausnahme, d.h. ein Wunder, nicht existieren." D. Reichenstein, Die Religion der Gebildeten (1941), p. 21). However, it is clear from the context that Einstein was stating only that miracles cannot exist in a domain (quantum mechanics) where lawful rationality does not exist. He did not claim that miracles could never exist in any domain. Indeed, Einstein clearly believed, as seen in many quotations above, that the universe was comprehensible and rational, but he also described this characteristic of the universe as a "miracle". In another example, he is quoted as claiming belief in a God, "Who reveals Himself in the lawful harmony of the world."
As quoted in From Yale to Jail: The Life Story of a Moral Dissenter (1993) by David T. Dellinger, p. 418
Disputed
Variant: There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle.
Variant: There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle.

Source: Selected Poems

" The $4.7 trillion pyramid: Why Social Security won't be enough to save Wall Street http://www.harpers.org/archive/2005/04/0080499" in Harper's Magazine (April 2005)

Source: Tatiana and Alexander

Letter to George Washington (1796); published in The Writings of Thomas Jefferson, 20 Vols., Washington, D.C., (1903-04), 9:341
1790s

The Bicycle Rider In Beverly Hills (1952)