If you ever find yourself staring at a hole marring an otherwise perfectly good wall, don't worry. Patching drywall is easier than it looks: you just need the right tools and a few basic principles.

Dear James: I just moved into an older house, and a lot of the drywall tape is coming loose and needs retaping. Why did it come loose, and how should I replace it? -- Randall N. Dear Randall: It is ...