There’s usually a particular sleeve or pattern that I might like, so I start with that idea; I’d drape the sleeve or segment that I thought about directly on the mannequin. Specific folds, the creation of a fabric hang, or a unique hemline might be best achieved this way. But sometimes, I simply allow the fabric to hold its own; it'll tell me where it wants to go...and I end up surprising myself with the result.
The fabric's optimal potential is best visualised on the mannequin: I'm able to smoothen out lines and creases, or splice and pin the fabric at just the right spots. Its soft stance is enlightening; I learn how a dress might fall down a woman's body lines, how it'd lean gracefully into her shape, and how it might feel on her.
A fair bit of calculated experimentation comes into play here — but via this technique, we're eliminating any unnecessary seam lines that might be produced otherwise.