Be there for them in the days as well as weeks, months and years following the death. Know that your friend will always grieve the loss but will learn to live with it and internalize the loving relationship that once was external. The use of euphemisms tends to deny the extent of the loss and the fact that one who was loved is dead. Help those who are in the process of grieving develop the rituals they need to get through those early difficult times. If the person who is in grief is suicidal it is your moral and ethical responsibility to refer them to a mental health professional.
Cliches are simplistic solutions to complex problems.
They make people suppress rather than express grief. Compare one griever's loss or experience of grief to another's. Encourage grievers to make major changes in their lives. Grief clouds people's judgment. Decisions made too soon after a loss may be regretted later.