With a market order you're letting the MM's drop the price, buy your stock, and take it right back up again. If the stock had moved up, and you want to insure a gain, but ride it higher if it goes higher, set a stop loss order at a specific price just below where the stock is selling for, if it comes down it will sell at your price. If it moves up, reset your stop loss higher. Eventually the stock will probably hit your stop loss order and you'll be out. On the other hand, if it reaches a point where you either want to keep it, or don't want it to sell to easily, drop the stop loss lower. If you really want to sell, put in a limit sell order that's at the price being bid and it will be sold without the risk of a market order where the MM's can play games with you.
Trailing stop losses are a good way to go if you're not in a rush to sell, but want out if it goes below a certain price. If you want to sell when it reaches a certain price you can put in a sell order at that price and it will be sold if it hits the price. When it's close to the price you may want to rethink it and raise your price, but it will sell if it hits the price you set.
Gary
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