The retrieval line (halyard tail) will run through the bottom patch first, up to the mid patch (if you have 3) then tie off to the top patch. When you snuff it, the top patch will be pulled down to the other two, and all 3 will go into the mouth of the snuffer sock first, then pull in the tack, head and clew of the spinnaker last.

So you need to measure how far it is from the top patch to each corner of the spin, to see how long of a sock you'll need. And remember, you can run the tail end of the sock under your tramp (deck), so it can be pretty long, as long as you have a way to attach it to the underside of the tramp.

The tail of the halyard will come out the back of the sock, then run back a little further, then up through a hole in your tramp/deck, and back forward to a block near the base of the mast, and then up the mast to the spinnaker head/block.

It's one big continuous loop, with some slack on the deck, so your retrieval line isn't too tight on your spin when you are running deep and have it sheeted way out.

When it's time to douse it, you simple dump the halyard out of the cleat and pull like mad on the tail, where it comes up from below your tramp, and that will pull the patches down and into the sock, with the clew, tack and head coming in last.

You will also have to decide how you want to run your tack line. There are two schools of thought on how to rig that.

Some boats are rigged with a separate tack line, others will put a small harken block at the end of their tack line and run the spin halyard thorough that, so as the halyard comes up and tight, it pulls the tack line out, and vice/verse when you snuff it.

With a big spinnaker like yours, I would run a separate tack line, otherwise I think the load would be too much to both raise the spin and pull the tack out at the same time. With a separate tack line, you'll want to pull it out first, and then quickly pull the halyard up. On the snuff, you get 80% of the spin in the sock first, then release the tack line and finish the snuff.

That will keep your spinny from becoming a sea anchor if you aren't fast enough on the snuff line.