Rock the glider rocker and try to pinpoint where the squeak is coming from. If necessary, turn the chair over and rock it. Watch the moving parts as you rock it and try to determine if there is a spot where two surfaces are rubbing against one another. The chair's wood or metal could be rubbing, or the chair's joints could be squeaky.
Locate the spot where wood is rubbing on metal or on another piece of wood. Rub a candle or bar of soap over the wood. Rock the chair again. Repeat the process if it still squeaks.
Find the spot where two metal pieces are rubbing together. Reduce the friction, and the associated squeaking, at these spots by spraying them with cooking spray or WD-40. Apply the spray liberally.
Locate joints in the glider rocker that are squeaking and coat them with petroleum jelly. Then use a hair dryer to heat up the area, causing the jelly to melt and run into the joint. Rock the chair back and forth so the jelly coats the joint. Repeat until the squeaking stops.