I have long admired the colorizing work done by several members of this forum but I was never able to figure out how to do it. Finally I decided to Google it and came up with this very brief tutorial
Colorize a Black and White Photo
Below is my first attempt (Mel Wright of the 1961 Cubs). The skin tone on the face is not quite right but the arms look very good. In any event I'm quite pleased with it although it took a long time. There may be shortcuts to do it quicker and I'll let you know if I discover them.