How to change the rubber in the windshield wiper of nissan altima?

the wiper is ok ,its the rubber which wipes water etc.which needs to be changed,can anyone guide me step by step?|||its easier just to replace with an anco quick fit wiper.|||You do not want to do that. Just buy a new blade from AutoZone or another Auto Store....Fact is the rubber inserts are almost as costly as a new blade. AND can slip out and the raw metal blade can scratch your windshield.