I use self vulcanizing plumbers tape (peel off the white strip stuff that
sticks to itself permanently when you overlap it) and one or two black cable
ties at the finishing end. (to hold it until the chemistry bonds them at the
molecular level - time depends on temperature)

when applied to clean surfaces, and you wrap 'up' so dripping water rolls
over the seams and not into them, it's leak-proof.

¡Ciao!