There are people that are actually good with shorting the market and it work very well them but here is something you need to understand about the market, time is everything you need to open a position in the market, when we are in the bull run, there are more opportunities of long position for market to go up more often than for it to go down and most of the times it quickly retrace anytime the market dump but there is risk as well.
Likewise it's healthy to short a market during a beer run, this is when you tend to make more money and it has it own risk, if you don't have liquidation price far from your mark price, you will lose money quickly because there are times we do have market squeeze when beers and bulls tend to liquidate each other account and it's the exchange that enjoys the fees been burnt for this operations.
Making that kind of profit from shorting isn't that common, and we should consider that when we are talking about this. I am not saying it is not possible, of course it is possible and can be done, it is just not that common and because of that it is not suggested. Obviously if you are great at what you do then you could make a good profit, and you should probably consider that as your main source of income if you are good at it because one can make so much profit from it.
However, if you do not know what you are doing, or haven't made a profit from it so far, then I would suggest staying away from it because you could lose so much more and very quickly as well, I have seen people lose entire savings in under an hour.