1. This is derived by dividing a company’s share price by its per-share sales. I use this ratio basically because it uses data which is not tinkered with as earnings can be, and found to be quite reliable.
2. Price /book ratio: This is not a commonly used valuation indicator I use this as it is quite reliable and the modified version known as Q ration is even better.This ratio is derived by dividing the share price by its book value.
3. The Q ratio: Nearly the same as the one given above except that instead of using the book value the replacement value of the company's asset is used.
One can use the regular ratios like price/ earnings, modified cyclical P/e ratio ....need specific analytic tool? do let me will try and help you with it.Once you do get into a habit of doing such analysis, your decisions become more informed and your calls less riskier.The data required is very much available in public domain and should not be hard to find.