Development by inspection is obsolete. It was used in the distant past (in other words, before about 1930) when films or plates were much less sensitive in general and almost completely insensitive to red. If attempted today, with fast panchromatic films, you will fog the film, no matter which safelight is used. Development by time and temperature is standard and recommended. It takes lots of experience to develop by inspection, and as I said today's fast panchromatic films do not permit it. They will fog. Kodak and other manufacturers used to make orthochromatic (non-red sensitive) films and plates, which were offered until about 1980 (though a few special-purpose ortho films are still produced for copying, where red sensitivity is of no value). A good example of the old discontinued films is Kodak Super Speed Ortho Portrait film.
This film could be handled under a Kodak Series 2 safelight (deep red). This was not for development by inspection, but rather for ease of loading into film holders. Ortho films were preferred for male portraiture and for ease of handling, since a dark red safelight could be used. Ortho press films were also used where red sensitivity was not important. These films have been discontinued for decades.
At one time, when photographers coated their own plates and exposed them while they were still wet (wet plates had to be exposed very soon after coating) development by inspection was standard: The sensitivity of the plates was less consistent than with modern materials, and adjustments were sometimes necessary. But dry plates were introduced by the 1870s, and shortly thereafter wet plates were abandoned. All of these materials were insensitive to red, of course.
This article is informative.
The article by Michael Smith referenced above applies to large sheet film (8x10, 11x14, etc.) and does not apply to miniature or roll films. The best answer is, forget about it. It will not produce any miracles.