If I drain my water system the easiest way to prime the water pump for me is to fill the water tank to a depth that is higher than the water pump. Then I open a water faucet or any valve to allow Mr. Gravity to fill the water system that is empty of water. Obviously all pipes above the tank water level will remain dry, but the water will flow through the pump into the pipes and fixtures at or below the tank water level.
I never turn on any pump unless I am confident it has been primed. Some say it is OK, but I would prefer to not take a chance.