Please read The Five Rules for Successful Stock Investing by Pat Dorsey. It is an excellent manual for investors and gives the best introduction on how to go about analysing a stock.
First try to understand the business by reading their annual report for last 3-5 years (atleast 3 years). Go through any brokerage reports that you may get about the company. Just don't look at the target price on the brokerage reports
Look for basic hygiene factors like ROE, ROCE are high; Debt/Equity is low; company makes consistent operating cash flows and profits.
Once you get a hang of what the company does, try to see if you can understand and project a range of sales and profit for the next 1-2 years. Assign a reasonable (start with being conservative) PE and see how the stock price might look like a year or two down the line.