Any basic fertilizer will make cycads happy. Something a little higher in nitrogren will help promote new fronds. Generally they only make one flush of fronds a year, but in climates with longer growing seasons it will probably make 2 once they are established if they are happy and they can make at least a dozen fronds in a flush once they get a older!
I hear people water with epsom salt occasionally (not the same as table salt) to keep their sagos green. Usually they are either getting ready to flush, or are deficient in some kind of nutrient if they are yellowing this time of the year. They tend to yellow more in pots than when they are planted in the ground, a good fertilizer will help keep them from yellowing further most times, but it will never undo the yellowing that took place (You'll have to wait for a new flush).
Good luck!
-Alex

Thanks. I have heard of Epson Salts. Can they be found in the Supermarket and can it be used on any palm (like Cocos and Bangalows).