Don't trade on margin, which is required for shorting. You need a few years under your belt before delving into shorting. If your asking this question I assume you are new to trading stocks.
Get good at just buying and selling first. Don't try to learn to much all at once. Focus on the basics like technical analysis and fundamental analysis.
Even us pro's get nervous going short... lol.. no need to put yourself through that just yet.
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