Some choose to see The Fool as our hero. The little guy who starts out at the beginning of a big adventure, naive and innocent in the extreme, about to fall from the edge and into the trials and triumphs of life (as represented by the other cards). This character emerges from the other side only through downfalls, risks and learning lessons from his mistakes. I don't necessarily see anything wrong with this interpretation but it's certainly not the whole animal. For one thing, we can be blinded by a foolish idea or indulge in regrettable behaviour at any stage in our life, no matter how much wisdom we're steadfastly sure we've acquired, and The Fool can be representative of that. But more importantly, seeing The Fool as the central character to whom things simply happen can lead us to allow the card only this negligible significance and see it as a passive draw that depends entirely on the other cards in the spread. This is downplaying a perfectly useful card.
The best thing about drawing The Fool in a reading is that no querent comes to me with a completely clean slate. They are not newborns, only just released from the womb and untainted by former experiences. They have baggage, like anyone else. The Fool, as the quintessential card of beginnings, is telling them to let that baggage go. Don't walk into a new land wearing your old shoes. The things you've learned, lived through been taught by others have shaped the way you address the present. The Fool is a card which acknowledges that fact and tells you to try and fight it because taking the blinkers off is going to open your mind and make your experiences richer.
There are themes of spontaneity and freedom, but the particular message is one of new pastures on every level. New interests, new connections, new information. Take in all of these new influences, enjoy them, but stay light-hearted and don't make lasting judgements or decisions. The Fool represents a very flighty, fun-loving influence. Anything could happen. It's definitely not the time for decisively taking a particular path but rather for seeing what interests you and following your nose.
It's a shame that The Fool conjures up certain unsavoury images of a bumbling idiot. Certainly some of the guide books that came with decks I've owned have described the character of The Fool as an arrogant or air-headed sap who believed angels would catch him if he walked off the edge of the cliff. I prefer to see The Fool as more of a travelling poet. A romantic idealist who, while he might have fears about the nature of reality, also possesses an incredible ability to be inspired by every area of life. It's important not to hoist too much responsibility or expectation onto this figure of joyful and carefree eccentricity. While he might not yet have the experience required to create something stable and long-term for his own future, he still has much to teach us about how life's twists and turns can fill us with ecstasy rather than drag us down.