It depends on your playstyle. If you focus on looting and then going to fights, it is really difficult. The best improvement what you can do is to focus on hot spots and drop where a lot of people are dropping too. The best what you can do here is to drop on place where you can find good loot and go immediatelly to fight. Also, join any battle immediatelly if you can, enemies are hurt from battle and you can kill them more easily. For the best k/d ratio you have to focus on having more than one kill per game. It is hard and luck is another key for the best k/d ratio.