That small but potentially great idea you had this morning? Although it seems unforgettable, you might not remember it this evening. You probably won't remember it next week.
Write it down.
I carry around a Moleskine notebook to jot down good ideas that occur when one would least expect them. It is seldom out of reach. I keep the old notebooks and periodically scan them to trigger memories of past thoughts or to nudge me into new ones. Upon reflection, not all of the ideas are worthy of action and yet even the marginal thoughts may lead to one that is promising.
Despite having a very good memory, I have found that the most creative ideas are as soft as feathers. Unless quickly captured, they can float away.
And in a competitive world, you don't want to lose those feathers.