I usually try and abide by a two print maximum when mixing patterns since any more than that becomes a bit too busy.  I mixed basic grey stripes with florals for casual parties this weekend though and found that a third pattern can be worked into the equation when it falls into the same color family — like a great pair of grey snakeskin wedges.

{Target t-shirt; H&M skirt and necklace; Nine West wedges; Ray Ban sunglasses; vintage/misc. bracelet and rings}