Decide at what percentage you will take profits, etc. You might decide to protect 3% of your profits when the stock rises 10%. Once a stock rises 15% you might decide to protect 10% of your profits. When your stock rises to your target 20 to 25%, revert back to rule #2. You must decide what is comfortable in the profit department. The important thing is to make some decisions. Make those decisions a part of your system and govern your system with your discipline.

A personal note on profit taking: There is no question that if you are disciplined enough to follow a plan such as the one outlined, it will improve your results. However, most people will not follow rules. Why? Most people cannot stick to rule #1. Winners cut their losses short and move on to the next trade. Also they hold no grudges against any security. Losers hold on to falling stocks mostly because of psychological issues until making a rational decision has long since disappeared from their psyches. Only time will tell whether you have the inner strength to become a winner.

Here's a simple calculator for setting stop loss points. You can change following fields:

Number of Shares, Purchase Price, New Price, Stop Loss percentages, Lows of previous days