Watch the Tapping online guitar lesson by Stu Hamm from Stu Hamm U: Solo Bass
This technique will play a big part in solo bass playing, and is covered thoroughly in my TrueFire course "Stu U: Tap Bass". Here let's just look at the most basic application. In Bar 33, tap down on the 10th fret of your string with your index finger and let the G ring. You'll need to hit the string straight down at a 90 degree angle to get a good tone. Then in bar 37, play the G as well as the D on the 12th fret of your D string with your ring finger to play the fifth. This will take some practice if you've never tried it before, but be patient and practice and it will come to you! The final note of this piece will be tapped by your right hand as well.