We live in 2 planes - the 1st is life, the 2nd is the full stop to life or death. We understand life. So, we know how to deal with it. We can't understand death. It is a mystery. It's timing is a mystery. And the future after it is too. It is natural to fear the unknown, hence death is feared by most of us. But part of this fear comes, because we are not prepared for death. We took death for granted, rather we took our life for granted and never factored death till an old age. This casual approach towards death makes it an unpleasant customer when it arrives. Death is the ultimate reality. When we don't prepare for this reality, we lead our lives out of touch with reality.
Fear of death has 2 main parts to it - 1. the fear of the unknown, and 2. the lack of preparation for it. It is virtually impossible to remove the 1st part, the fear of the unkown. If you are passing through a black tunnel in which nothing is seen, you are bound to feel nervous or tentative. It's natural. There is nothing to be ashamed of. The 2nd part of reducing fear of death is to prepare for it. Surely, you can't prepare for it by knowing it's timing, because that is not known. But one can prepare for death by carrying the imprints of the practice of human values and a virtuous life on one's soul. There is no better preparation than this, no better protection. In the darkness of uncertainty, one's goodness will form a shield of protection against the possible harmful effects of retribution. Negative retribution or karma will be minimized as the positivity of our humanity will be stamped on the soul.
Hence, our conclusion is that fear of death is natural, but can be minimized through adequate preparation. We have enumerated earlier the steps we need to follow. To make a conscious attempt to follow good human values, needs us to constantly remind ourselves that death is round the corner. The wisest men always remember their death often. Remembrance of death will remove your pride, ego, anger, and jealousy. Your soul will be purified only to do good then. You will feel light, without burden, and blessed, and enjoy the inner peacefulness of following human values. To do this, close your eyes, and say to yourself 7 times a day, "this is my last breath".