Both methods work, however I have found most pilots find it easier to side slip particularly for the high wing Cessna's. For the PPL I teach students to crab down to about 300 feet AGL and then transition to a wing down sideslip. This gives them enough time to get things stabilized prior to the flare.
As they gain experience they can delay the transition to lower altitudes until they can carry the crab right into the flare rolling the into wind wing down while simultaneously using the rudder to align the aircraft with the runway. Done well this provides a very graceful smooth touchdown.