1. Fixing Under A Wig - 1

This is the easiest situation to deal with, as almost the whole cable can be concealed under the wig and the capsule of the microphone can be left in the ideal position on the forehead. The only problem is how to deal with the cable run  from the end of the wig cap to the neck of the costume. Obviously, if the character is dressed in a high collar, this is easier than when the character has a low neck line.

The pictures below show how the microphone is fixed and taped to the neck line.  The character is 'Evita' from the show of the same name - you will note that she has two microphones - this is simply to protect against possible failure of one of the mics so a spare is in place - Evita spends most of the show onstage and carries most of the action; if her microphone was to fail, the whole show would be compromised.