Start with gluing the end of the string to the bottom of the vase. Place the twine on the glue, then hold it until the glue gets dry, and the twine stays in place.
Afterward, continue wrapping the jute around the pot, adding glue every couple of rows. Make sure you pull the twine tightly the whole time because the glue will hold it better then.
You don’t have to cover the whole terracotta pot in glue for the twine to stick to the vase. Every two rows will do the job. If your pot is more curved or has an unusual shape, use a little bit more of glue to secure the twine.