Hi, while searching through the net, I found interesting long sling, that should been used in Spain and mentioned in Don Quijote, I decided to try it, just out of couriosity and have few questions.

It should be a 3 strand braid, retention cord 120 cm, as it has no finger loop, Im thinking of Matthew Walker knot... Good choice? (Better suggestions) also applies for the release cord, which should be shorter, 100 cm, and thinking of knot to finish it, would like something decorative, if it wont be too uncomfortable.

The pouch should be about 17 cm, and there should be added cord on each side, so the pouch has same width as release and retention cord.

My question though, as I dont know the math well due to being unexperienced, how far from the knot should I add the additional cords on each side?

Also, do I use a flat braid, during the whole process, the part close to the pouch seems wider to me, so I do expact 6 strand flat braid?, but do not know, when to attach the other cords to the 3 I am braiding of.

Im little bit confused as a beginner, but really would love to make or try... This sling, as its being very attractive to me from several reasons. Im fully aware that itll have probably bad accuracy, especially in hands of beginner lol, but as mentioned, Im Cervantes admirer, and as much as out of pure exoticity like I would like fe to try some sling used in Pacific islands, Andes..., same way attracts me this in particular, just bit different reason....

I will be using 550 Paracord to use my last supplies of it and next on I would love to ho traditional way, for this one I will use Paracord as Im new and so far its the only material, I am at least a bit familiar with.

Excuse my long post please, the only thing Id need to know, when to add additional cords, bit to explain how to implement it into the ones Im working with, and confirm, if my view was correct and for a short part is used 6 strand flat braid.... And approx, if the pouch should be +-17 cm, when do I add the cords into the 3 strand braid.

Thanks a lot to everyone guys! Wish You nice evening

Can you share the image that you found? There are a lot of designs that fit your description.

Is it this tutorial you are referring to?
https://slinging.org/51.html

As Stabyhoun mentioned, if you share the image of what you're looking at we might be able to give more specific answers.

On the subject of splicing in paracord, it's pretty straightforward.  Just add a piece to one of the existing strands so it's doubled up.  Once you've braided a bit more, you can cut it off and melt it so it holds.  Make sure to leave a little bit (a quarter inch or so) for melting when you cut it.  This is a 4 stand round braid, but you can see an example of adding a strand here: https://youtu.be/8OPuCrF3TIg&t=708.