Stocks, toe tied so her feet couldn't move, and give'm a good scrubbing with a hairbrush. Would also nibble her toes while tickling both her arches at the same time.
Nylontickler61 - I do like the idea of stocks. Ideally she is in a sitting position so she has to watch as you work her feet over. I also like the idea of lots of verbal teasing as you are tightly securing her feet and toes, telling her how much you are going to tickle her feet and how you are Not going to stop.
Qwill - it depends. Sometimes she is more ticklish than others. More so after a few glasses of wine! My favorites spots are her feet (of course) and her legs. Her sides are very ticklish but that annoys her.
The stocks are great...I made a nice pair for my wife and others to play but once kids came along, I dismantled them as I did not want them asking questions... ;-)
Tie the toes of her nylons together, and then to the arm of the chair her feet are resting on. Then, very slowly run a single finger from heel to toe, repeating on both feet.