First, use a probe or needle to remove the old O-ring.
Pull the O-ring off.
Use a rag to clean the O-ring track of old lubricant and debris.
Take the new O-ring and pull it lightly onto one end.
DO NOT stretch the O-ring longer than necessary as it will cause
the O-ring to seat too far into the groove and will not seal well.
Loop the O-ring over the other end of the groove.
Use a pencil or flat long object to press the O-ring into place.
The O-ring should be evenly distributed on all sides.
If it is not - reset the O-ring so it is evenly distributed and
will make contact with inside of chamber on all sides.
Make sure the O-ring was not pulled too tight onto either end.
Lubricate with Petroleum Jelly. - The lid is now ready for use.