NPM needs updating?

Still working this all out.
Node Red wasnt working too well so I seem to have managed to update Node Red (and the pi) in general, but now my palette manager is missing.
I have noticed this in the startup log which I assume explains this:

27 Oct 22:18:09 - [info] Palette editor disabled : npm version too old. Requires npm >= 3.x

So how do I update the NPM bit ?

Please follow the documentation.
It should update npm/nodejs