Buy puts and calls These trading options can help you to reduce risk in your trading strategy. They do however expire worthless if not exercised. Since you would be consistently buying over the long term your purchase price will be averaged over the course of your purchases. Your time frame is very important. It's easier to ride out a market decline when you are committed to investing for a long-term goal.
Risk tolerance is also an issue.
Your own level of discomfort with market swings should influence how aggressively or conservatively you invest. I'd like to sell a stock since I have a good profit, but I don't want to pay the taxes. Sell the stock and pay the taxes. If you don't make any money, then you won't owe the government anything. Some technical indicators such as RSI can be helpful in locating approximate local maxima.