Hands off yoke 
Do 180&amp;deg; turn, but is not always the best option. Climb? Descend? Combination? 
This is an emergency 
Get on ground, now! 
Worry about consequences later, after returning back to the planet 
ATC can help, but you have to get yourself out of it. 
Move head as little as possible. If have to move the head, do so very slowly while fixated on attitude indicator. 
The flight instruments MUST be in working condition in order for the student to have a chance at surviving inadvertent IMC. 
Dark night, no moon, over a barren landscape or ocean can be actual IMC.