Gross huh? Nah it’s line drawings.
Folks ask if they can express their dog’s scent glands (anal glands) at home and I say “YES!” because frankly, it’s gross and I don’t usually “want” to do it. So to those intrepid souls, have at it! Be aware you can hurt the dog. You can get bitten. Your dog won’t look at you quite the same ever again.
The two concepts are: The glands are at the 4 oclock and 8 oclock positions, and with some lube and a latex glove you can go through the anus and find the glands on either side. Then, much as you would get a finger past a marble in a shot glass to remove it, you pinch the anal gland between your index finger and your thumb (on the outside) and “pull” the material out of the gland “up” to the anus opening.
See this document. anal_gland_expression_final_jvs_2019