Basic motive is to earn profit in short term holding.
you can do that by discounting its intrinsic value or discounting from 52-weeks stock price data.
How to Calculate Intrinsic Value
http://www.stock-investment-made-easy.com/calculate-intrinsic-value.html
Margin of Safety from Discounted Intrinsic Value
http://www.stock-investment-made-easy.com/margin-of-safety.html