Splicing is a super handy technique to have in my box of tricks, and the method can be adjusted depending on the style of rope your working with.
Splicing essentially creates a loop the size of your choosing at one end of the rope, without compromising the strength of the rope. There's no melting or sewing involved!
I'm going to be totally honest right now - when I splice double braid nylon rope like this, I'm not entirely sure exactly how it works. So if you have questions, head on over to Google!
I believe this video is actually of me working on the extra long custom reins I made, I'll link the related post!