For example, if the margin is 50%, it means you have to have at least cash at 50% of the value of the shorted stock. So, in your account, you have 150% of the value you borrowed in cash. If the price of the stock goes up, you need more cash to keep your position, or your position will be closed out at your cost.
In order to protect your investment, there is tons of strategies and tools you can use, like options, futures, and other exotic derivatives. You can also use these vehicles to speculate, but it is very risky. Only those professionals can actually manage that. You might be lucky sometimes, but at last, you will have nothing if you have no relevant risk management.
In order to protect your investment, there is tons of strategies and tools you can use, like options, futures, and other exotic derivatives. You can also use these vehicles to speculate, but it is very risky. Only those professionals can actually manage that. You might be lucky sometimes, but at last, you will have nothing if you have no relevant risk management.