A note-taking system without notes doesn’t make much sense. You have to accumulate notes. Do they need to be good? Do they need to be perfect? No. They won’t be. Not on the first try.
But they do have to be written. What gets them written? In order for them to be written by choice, they have to be interesting enough - or the process of creating them has to be. You might be forced to write them, then maybe find a way to make it interesting.
In any case: Do start by writing notes.
(One of my favorite internet people is Merlin Mann who writes this on the first page of all his paper notebooks. This is the right approach to digital notes as well. Get it down first. Make something out of it later. This is a flickr-embed of Merlin’s photo. No copyright intended. See his Album for more.)