Pool pumps are 'self priming'. You can dump a bucket of water or run the hose into the pump basket if you like, then replace the lid after cleaning and lubricating the gasket with Pool Lube, secure it tightly, and then start the pump. It should prime in a minute or so. Especially if your pool equipment is not more than a foot or two above the pool water line. Be sure to have your filter relief valve open until it shoots out water.
Reasons a pump loses its prime
One of the most common reasons a pump loses its prime is the pump lid gasket. Sometimes, they will seal well under suction but after the pump is off, they don't seal as well so leak air in. Other possibilities are the pump drain plugs and filter. After turning off the pump, listen close to the filter to hear any bubbles rising up. Otherwise, lube the lid and drain plug gaskets with pool lube and see if that helps.