For your 6mm nylon tubing here is a trick to make it more PRO (lol)
Put a piece of electrical wire up it (to stop tube from collapsing) and heat it up gently with a heat gun and BEND it to suit your application

it then stays in position perfectly and looks sick as fuck
I have mine routed in all kinds of places, and in hot environments I sleeve it as well. Little tricks you learn over 20 years