A pool should be vacuumed every week to keep water clear and reduce the amount of chemicals you need to add to it. There are many types of pool vacuums. If you have a manual design, work it back and forth all over the surface of the pool like you would if vacuuming carpet. It's good form to slightly overlap each stroke. Check the filter each time you vacuum, and clean it if necessary.
But vacuuming isn't the only maintenance that should be done once a week. Brushing the walls and tile helps minimize algae buildup and calcium deposits so they don't fester and become larger problems. The material your pool walls are made of dictates what kind of cleaning tools you should use. Select a stiff brush for plaster-lined concrete pools and a softer brush for vinyl or fiberglass walls. For tiles, use a soft brush to prevent scratching or degradation of grout. A pumice stone, putty knife or a half-and-half mixture of water and muriatic acid can also work well.