If you're going to gamble on $TSLA, shorting is probably the worst way to do so. It has unlimited downside (well, at least as much your broker allows before margin calling)

If you want to gamble, buy put options and size according to how much money you're okay with losing (the premium is all you pay)

True short positions are out of reach for basically any normal investor except those with completely broken risk tolerances (selling unbacked call options), eg the degen gamblers of r/wallstreetbets.