When it’s a bull market, investors use a variety of strategies to make money. Some of these strategies are straight-forward examples of buying a stock at one price and selling it at a higher price. These strategies follow varying degrees of risk for investors.Related: NEW TAX LAW WRINKLES FOR INVESTORSBuy And HoldPassive investors typically follow a simple buy and hold strategy. This involves buying a stock, bond, mutual fund or ETF and holding it for a year or more – or until it is clear a market reversal is on hand. At this point they sell the security and take a profit. This is the safest way to trade or invest in a bull market.Buy And Hold On Increasing PricesThis strategy is slightly more aggressive and requires the investor to be a more active participant. Under an increasing buy and hold strategy an investor makes the decision to increase his holdings of a stock based on a rise in the price of that stock. This could involve, for example, buying additional shares every time a stock goes up $5 in value. Once the stock reaches a predetermined level or sees indications the market is topping out, the investor sells and takes a profit.Retracement BuyingAn even more aggressive strategy involves carefully watching the market for the times when a stock moves downward before going back up. These fluctuations are common and retracement addition allows you to add to your position during a downward move (or retracement) based on your conviction the stock will eventually move back up. The decision to sell is the same as with other strategies – either at a predetermined price or when you believe the market has topped out.Trading Both SidesIf you want to take advantage of both sides of market swings – up and down – and are comfortable being quite aggressive, full swing trading may be the way to go. With this strategy you use buying and short-selling positions to make money as stock prices go down and again as they go back up. As you might imagine, only experienced traders should attempt this type of investing and only investors who have the time and ability to stay with their trades on an almost full-time basis. In a true bull market, of course, it may make sense to take larger buying positions than selling positions to weight your trading in the direction of the overall bull market.Related: FUNDING TRUMP’S INFRASTRUCTURE PLANOptionsOptions are not specific to bull markets but are used in bull markets in specific ways, especially at the beginning of a bull market. For example, a Buy Call Option allows you to control more shares of a stock with less capital at risk. The amount you have at risk is whatever you pay for the call.You make money when the stock price rises ahead of the expiration date. Another strategy called Selling Naked Puts involves collecting a premium for selling contracts when the stock price remains above the strike price, rendering the contract valueless and allowing you to retain the whole premium. There are other options strategies, each increasingly more aggressive and risky.