Raking allows you to play fast notes on consecutive bass guitar strings. It's usually executed from high to low string (G to E). This video takes a groove from my book 100 Funk Bass Grooves and breaks down the technique as well as the notes used.
Scroll down for the PDF and drumbeat backing track.
Funk Bass Example
This is Example 1b from the book (which you can learn more about here).
Drumbeat Backing Loop
This is a drum file that you can drop into your DAW and loop. At first, practice without the drum loop (or metronome) until you get the line together. Then bring in the loop and practice playing in time with good groove and feel.
You should practise this kind of thing everyday to get your timing together (one of the most important attributes for any bass player!).
There are many more bass guitar techniques you can use to express yourself fully...