Stocking method with catheter.

Instead of using a stocking, try using a simple small rectangle of cloth (or cut out a piece of stocking).
Fold in half, and place over your penis with the single fold being next to your belly, then wrap it around your penis to form a tube of material around it.
Then as with a sock, first pull both layers to pull your member into the tube, and then pull on just the outer layer to slide it off your skin. The material not being a enclosed tube will mean you can unwrap it without interfering with your catheter.

 

Not sure how your catheter attaches, but I can put mine in, then the stocking, then the ring, then the cage up to a point. Remove the stocking (through the bars near the end, not the actual pee hole of the cage) so that everything has moved down (almost) where it needs to be. Guide the end of the catheter into the pee hole, apply the locking cap, then secure the cage to the ring.
My catheter only has a short amount of threaded section which needs to go through the cage, so the stocking has done 90% of the job before I set it in place. The only difficulty I have with this sequence is that there is little or no friction in the urethra, so the catheter can spin instead of engaging the thread of the cap.
Hope that helps.
Cheers

 

Inserted my urethral for the first time tonight, new cage also. Took a bit to get it in. Not comfortable, but I think I’ll get used to it. Almost 5 hours at this point. Want to see if I can make it thru the night on the first try. Probably switch back in the morning as I work tomorrow.