Hi KW - I guess you will have been exposed to all the usual valuation methods. I simply use home-grown forecasts and DCF's and don't usually get too clever about it. I also pay a lot of attention to the one year growth forecast - if growth slows or turns negative, then I look more closely at whether to sell and am less likely to buy.
I guess the only way investing ever made sense to me was if I could place a value on shares and decide whether a buy or sell was a good deal or not. It's generally worked okay for me, although the consequent emphasis on buying "cheap" has it's downsides.
I tend to buy with a 2+ year view and don't tend to trade in and out, although I often add to stocks I decide I am happy with and reduce those where the amount of money held is larger than my enthusiasm for the stock - often these are multibag investments that I reduce but still hold a portion of for a while longer until my remaining emotional attachment wanes.
I accept that valuation is as much a "black art" as charting - but they both increase the odds of successful decision making. While it is appealing to seek the perfect method, the reality is that nothing will work all of the time - and even defining whether a decision was correct or not can be difficult, since a decision is often "right" in one time frame and "wrong" in another.