As far as my readings into Chaos Magick go, you do that, but you shouldn't simply forget the sigil; focus on it, over a certain period. See what happens. Experiment with wording, symbolism, time, everything. Chaos Magick is a lovely thing, really.
Also, although it can be difficult to find, if you can get your hands on a book called "Practical Sigil Magic" by U.D. Frater, that should have good information. I've yet to order my copy, so I'm going off the opinions of others.