These home-grown methods typically suffer from two flaws. First, they do not cut out enough visible light. Second, they provide little protection against ultraviolet or infrared light. The only safe method for viewing the Sun directly is using No. 14 arc-welder filter or a metallicized glass or Mylar filter. A local hardware store or construction supply store should carry or know where to obtain arc-welder filters.
Many astronomy magazines carry ads for solar filters.
Whatever filter you use, inspect it to make sure it has not been damaged. Even a pinhole can let through enough light to cause injury. Never use an eyepiece filter, which can overheat and crack. If using only one side of a binocular, cover the other side. An alternative way to view the sun is in projection.