My online trading experiences

#1
Being a green horn in day trading, I am still earning my spurs. I have just lost Rs. 2000/- due to the Market crash triggered by the Chinese market crash!!
I did not know how to put a STOP LOSS on the scrip i had just purchased and was help less while the stock price plummetted. I need some guidance as to how i should use the stop loss option.
Thank You.