Probably the best bet is use the saks.com website and their 10% off coupon if it's still working.. and I think there is free shipping if you follow up your order with a call.
I'm told by SAs at my local Bloomingdale's that their F&F event (also 20% off) is around mid-November. When you pre-sale the items before the actual event, there is no requirement (offer, card, etc) whatsoever; when the event has started, some place orders over the phone to bypass the requirement. The same goes for my local Saks, I'm not sure about other locations though. Brand restrictions sometimes vary from store to store. My local Bloomingdale's allowed all the brands (no Chanel & LV here) in handbag deparment during their F&F event a few months ago. As for Saks' most recent F&F event, Beverly Hills store included YSL but NY store didn't.
With recent events, many customers ask Nordstrom to price match.
Definitely do the Saks F&F thing. I went to the Saks in NYC and pre-purchased the MJ Stam in the Mouse color and am getting it 20% off. I think you can usually go to the store and chat it up with a sales person and they can give you the discount.