Cut a hole in the Mason jar lid with the pinking shears. Make it just big enough to fit the rubber stopper. Insert the rubber stopper into the top of the jar.
Punch a hole through the rubber stopper using an awl or screwdriver. Hollow out the stopper until you have a hole just large enough to insert the nozzle of the vacuum pump.
Squeeze fast-acting adhesive glue continuously along and inside the gap between the rubber stopper and the Mason jar lid to form an airtight seal. Place the item or substance being experimented on into the jar. Screw the top on tightly.
Place the nozzle of the vacuum pump into the jar through the stopper. Suck the air from the jar using the pump.