Ball joints, tierod ends, u-joints (Depending on what brand you use.) Also, give the hiems a good squirt of a teflon based lubricant like TriFlow brand lube.
*FYI* NEVER use wd-40 as a lubricant. It is a cleaner and will attract dust, and not provide lubrication at all.
If your tierod ends or ball joints do not have a zerk fitting *grease nipple* Get a zerk kit and install them. Drill a 1/8" hole on the cup side of the joint, tap it and install the fitting. You will not regret it.