Watch the Slide Tapping online guitar lesson by Chris Buono from 60 Electric Guitar Techniques You MUST Know
Slide tapping throws in legato slides within tapping sequences, making an overall amazing sounding legato scenario. The slides can go up or down or go back-and-forth – it's up to your creative fancy. They just have to have the same dynamic range as the rest of the legato run to sound the most effective.
Looking for inspiration? When it comes to how far all things tapping (including slide tapping) can go, a great player to start with is Ron "Bumblefoot" Thal.