Handy guide to the future provides a lifeline (4)
I believe the answer is:
palm
'handy guide to the future' is the definition.
(reference to palm-reading)
I don't understand the rest of the clue.
(Other definitions for palm that I've seen before include "Conceal in the hand" , "Leaf in part of the hand?" , "Underside of hand" , "may need greasing" , ""trophy"" .)