If the stock moves in the right direction after initial shorting of 10k. Short another 20-30K immediately. Wait till the stock moves closer to the Moving average. Cover the stock at this point.
Most of the gains up to 3-8 percent come during this time. Cover the stock when it moves closer to MA. If the stock moves further down after touching the MA, one can short again if necessary.
Day trading needs fast decision especially during the opening half hour. When choosing stocks that are deeply selling or buying one has to understand that the morning is the ideal time and if the stock moves in the right direction then after 5-10 minutes short or long in the same direction. Do not reverse direction and make stupid mistakes. Just follow the rules.