Zippered Pocket on your shell means.....

[Wise Old Owl]

Your pocket is the stuff sack... I have a Granite Gear and a LL Bean Shell (Breathable Rain Jacket) Both came with a stuff sack. So I never looked to try this. set aside the stuff sack and turn the main pocket inside out. Then stuff the shell all the way into the pocket. Now that the zipper is inside out use the pull to pull it closed. Even if this is a mesh pocket it generally works and now its in a small space and you can leave the stuff sack at home. The LL Bean has a key ribbon that is sewn in, and that becomes the carbine-er attachment to hang it outside the pack.

Hey in both cases this was NOT in the instructions.... So you got to try it!

The more stuff sacks you can leave behind..... Yea!

[WingedMonkey]

My REI rain jacket and pants both come with double tabbed zippers for that purpose (smarties even put their logo so it shows when turned inside out).
So then I started even doing it with any of my shorts that have rear zipper pockets. Works with some that don't, not as tight.

[Spokes]

Sometimes it's like trying to figure out a Chinese puzzle.

[STICK]

My SD rain pants came with a stuff sack, but it also came with instructions which said it could be stuffed in the pocket on the pants. So, I used the stuff sack for my ditty bag and stuffed the pants in the pocket...however, since then, I replaced stuff sack with a much lighter cuben fiber stuff sack, and the pants for a cuben fiber kilt...Saved lots of weight and leave the stuff sack and the pants at home... haha...