What I usually do if prices are falling most specially if the coins are very low, I would buy more coins from a much lower price and your total amount of couns would then be divided; the result would be lesser losses. Read or research on google about books or ebooks on trading.
When bitcoin drops you should keep calm, do not sell all the bitscoin you have. Prices will rise in the next few days. If you have the capital to buy bitcoin at low prices then when high sales will have money. Normal psychology players will worry if bitcoin falls for several days in a row.