Annual regreasing shouldn't be needed unless you routinely ride in bad weather but heavy greasing when you install the cups is needed. An alternative is to wrap the cup threads in a couple of layers of "Plumbers" Teflon tape prior to installation. It seals against all water incursion and makes the cups easy to remove later on.

You should secure the bb cup removal/installation tool firmly in place so it won't slip under torque. For a square taper bb, get an M8x1.0 mm (1.0 mm thread pitch, not the more common 1.25 mm) bolt about 40 mm long and thread it through the tool and into the hole at the end of the spindle. For a hollow spindle (Octalink or ISIS) use a qr skewer to lock the tool in place.