Start with a cm diameter clump of long grass, hold it at the 3/4 point of length, pinched between finger and thumb( short length on top), and turn the top upwards, away from you.
Still pinching, bring the lower piece up behind the now twisted part, and move your thumb and finger to this new meeting point and hold tightly.
Now twist that new top piece away from you, and bring the bottom back up behind, and repeat.
Feed in new grass as needed- this is why when starting your grass is not bent evenly in half- so new additions are variant and weak “links” don’t occur.
Rope making is very rewarding, and easy once you get the hang of it- the trick is to keep the twist tight for strength.
Morning Glory Vine Rope:
Another rope making method is for two people to work in tandem, one holding the centre point while one twists.
The morning glory vine shrank a lot as it dried and was not as successful as a finished rope, also inclined to mildew if twisted too tight (to counteract shrinkage) I would recommend experimenting with materials that are not extremely lush-IE: moisture content not so high.