The following information I copied from
The U.K. Sucrologists Club

How to empty a sugar packet:
Usa a sharp, thin blade such as a scalpel or Stanley knife.
Pierce only on the back and make a clean, small slit as close to
the crimped edge as possible.
Try not to tear or cut with scissors.
Shake sugar out and try not to wrinkle the packet.

How to open a wrapper:

Wrappers which are glued, such as the French ones, need great care and patience.
Ease each end open gently with the back of a small thin knife,
so that it does not cut the paper.
Extract the sugar cubes as soon as possible and then each glued section
can be gently eased apart with the fingers.