I think changing cartridges is "kinda fun"
If you are not having fun, you are just doing it wrong,,
Unscrew the top of the cartridge holding tube.
Hold the cartridge holding tube in your left hand.
Grab the spring loaded handle that is protruding from the cartridge holding tube.
Pull the handle half way out, then SLOWLY let the handle back into the tube.
The paper cartridge should remain partially protruding.
NOW,, find a target,, specifically the guy you do not like at work.
Aim the cartridge holding tube pointed at that guy's clean shirt.
(it is best to change cartridges early in the morning, while that guy's shirt is REAL clean)
Now, pull the handle ALL the way back, the piston should drop out of the paper cartridge,,
Make sure the piston is out, if not release the handle partially, and pull again.
NOW with the holder aimed at a clean spot on that guy's shirt, ACCIDENTALLY release the handle,,
The empty cartridge will FLY OUT of the holder!!
If you are within 10 feet or so, that guy now has a nice grease donut printed on his clean shirt,,
Apologize,, and QUICKLY TURN AROUND, so that he does not see you snickering!!
Drop in a new tube, pop the cap, screw on the grease gun,
and, enjoy your actions the rest of the day,,
it will be tough getting rid of your smile, when you see the "grease circle" on his shirt!!
Heck, if you were using the "RIGHT GREASE",, (MOLY is good)
many times the grease circle will still be there three washings later,,
Your smile might last two weeks, or more, from ONE GREASE CARTRIDGE CHANGE!!