Value Investing Basics

PEG
Typically a stock with a PEG of less than 1 is considered undervalued (A value investor would typically seek a PEG of less than one.) since it's price is low compared to the company's expected earnings growth. A PEG greater than 1 might be considered overvalued since it might indicate the stock price is too high as compared to the company's expected earnings growth

P/B Book value.
The book value is derived from a company's assets and is a more conservative measure of a company's worth. A P/B ratio of 0.95, 1 or 1.1, the underlying stock is trading at nearly book value. In other words, the P/B ratio is more useful the greater the number differs from 1. To a value-seeking investor, a company that trades for a P/B ratio of 0.5 is attractive because it implies that the market value is one-half of the company's stated book value. 

P/E
P/E ratio shows what the market is willing to pay today for a stock based on its past or future earnings. A high P/E could mean that a stock's price is high relative to earnings and possibly overvalued. Conversely, a low P/E might indicate that the current stock price is low relative to earnings.

Free cash flow (FCF)
Free cash flow shows how efficient a company is at generating cash and is an important metric in determining whether a company has sufficient cash, after funding operations and capital expenditures, to reward shareholders  through  dividends and share buybacks. 

Free cash flow can be an early indicator to value investors that earnings may increase in the future, since increasing free cash flow typically precedes increased earnings. If a company has rising FCF, it could be due to revenue and sales growth, or cost reductions. In other words, rising free cash flows could the stock reward investors in the future which is why many investors cherish FCF as a measure of value. When a company's share price is low and free cash flow is on the rise, the odds are good that earnings and the value of the shares will soon be heading up.

Debt-to-equity ratio
The debt-to-equity ratio (D/E) helps investors determine how a company finances its assets. The ratio shows the proportion of equity to debt a company is using to finance its assets. 

A high debt-to-equity ratio doesn't necessarily mean the company is run poorly. Often, debt is used to expand operations and generate additional streams of income. Some industries, with a lot of fixed assets such as the auto and construction industries, typically have higher ratios than companies in other industries. 

Too much debt can pose a risk to a company if they don't have the earnings or cash flow to meet its debt obligations. 

Intrinsic Vale
Many methods are used to calculate Intrinsic value.
When figuring out a stock's intrinsic value, cash is king. Many models that calculate the fundamental value of a security factor in variables largely pertaining to cash: dividends and future cash flows, as well as utilize the time value of money. One model popularly used for finding a company's intrinsic value is the dividend discount model. The basic DDM is:
Where: Div = Dividends expected in one period, r = Required rate of return
Value of stock =  Expected dividend per share /  (Cost of capital Equity / Dividend growth rate )  as Value of stock = D / ( r - g )

DDM model
current share price of xyz is $25
want 12% return per year for xyz.
xyz pays dividend $3 per year, expected growth 4%/year

as per calculation (3/(.12-.04) = 37.50) it's value is 37.50 so now xyz  is undervalued.

https://www.investopedia.com/terms/d/ddm.asp

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