The seven of swords is for me one of the harder cards in any tarot deck to understand and come to terms with (the five of swords would be another). The card as depicted by Pamela Colman Smith under the guidance of Arthur Waite is equivocal to say the least. I remember reading an interpretation of it in a particular book that I won't name, and thinking: "What? I don't get that from this picture!"
The Smith/Waite version shows a young man carrying away quite a lot of swords from a group of them set out before an empty tent -- in the distance, several indistinct figures are carrying on about something, unaware of what's happening, presumably to their swords. The young man's attitude and the look on his face suggests that he is stealing them, more specifically that he is Snatching a Cunning Victory from the Jaws of Defeat.
The keyword that Aleister Crowley used for the card in his beautiful and notorious Thoth deck is "Futility." Well, now, that was no help at all. Much closer to my feelings about the card is the version that Christine Payne-Towler and Michael Dowers created for their Tarot of the Holy Light (a favorite deck of mine all around). It shows a Quick Brown Fox making off with a hen in its jaws, while a rooster claws him and snaps at the back of his neck. The matching text in the book that goes with their deck suggests two possibilities: that it's time to keep an eye out against cunning adversaries who are out to plunder your hen coop, or that it's time to get inventive and clever yourself and figure out a way to get what you need in order to survive.
I don't have any problem admitting that my first attempt at this card design was an outright failure. "Duplicity" was the keyword that I started with, and the finished design was just... pedantic -- exactly the opposite of what this card needs. This version is more focussed, the keyword is more accurate to what I feel the card is trying to say, and the image now adds its own unique twist to the card's meaning: the one clown is literally stealing the thoughts and ideas of the other. Depending on whether the card is in its positive or negative aspect, it could be time for you to take something away from another's example, from another's thoughts or philosophies, or it could be time to watch out that others not take credit for all of your ideas and hard work. Either way, the time is right for an audacious move.