Wet a clean cloth with some lukewarm water and wipe down the leather furniture, to remove any dust or debris. Allow the furniture to sit for about an hour so that is completely dry.
Boil 11/2 cup of linseed oil in a pot for about five minutes on a medium heat setting, then remove from heat and let it cool to lukewarm for five to 10 minutes.
Mix in 3/4 cup of white vinegar with your linseed oil and pour your mixture into a plastic bottle with spray nozzle top. Securely twist the top closed to prevent leakage.
Spray a clean sponge with your mixture with about three to four squirts and begin wiping down your leather furniture. Re-spray the sponge every couple of minutes and continue rubbing the furniture down with the mixture until it is all covered.
Allow the oil and vinegar mixture to sit for half an hour, and then wipe off the furniture with a clean warm rag.