Pumping water is integral for many people to run their homes. If you have a well or a cistern, a pump is key for continuing to have access to that water, and when the power goes out, having an electric pump does you no good. A hand pump can be very convenient as a backup for an electric pump, useful for camping or making a functional ornament in a fountain. You need to make sure it is primed and ready to be used, so you always have access to the water you need.
Remove the bolts holding the handle to the pump with an adjustable wrench. Pull the lid over the plunger off, and slide the plunger out of the diaphragm.
Grease the inside of the diaphragm with a small amount of faucet grease from the top of the plunging area to the bottom. Pour some water through the diaphragm of the pump.
Insert the plunger back into the hand pump and pop the lid back on. Put the bolts for connecting the handle to the plunger back into their spaces in the pump.
Grab the handle on the hand pump and move it up and down until water comes out of the spout. Depending on how far away the water source is from the spout, it might take several pumps.
Some shorter hand pumps are self-priming and do not need water poured into the diaphragm. You only need to make sure the bottom of the pump is submersed in water and start pumping. You might need to grease it once in a while, though. Even with a shorter hand pump, if you go for a long time without using it and it is not working properly, try pouring some water down the spout under the lid to wet the leather or rubber on the base valve. It might be letting air past, and a little water can fix that.