You'll notice that the enable Bass sections on left-hand positioning for electric and acoustic bass vary about how many semitones can be covered using 4 fingers. This is because an acoustic bass has a longer scale neck.
The guidelines for electric bass are:
Use one finger for each fret (i.e. 4 frets for your 4 fingers).
When moving across strings to play common intervals like a perfect 5th (2 frets up and 1 string up) or an octave (2 frets and 2 string up) it is easier to use you index finger and little fingers.
Your left thumb should be positioned behind your middle finger, about half way down the neck.
Many songs are based around a fixed position where your index finger covers the root note. e.g. if you're playing in the key of G your index finger would be on the 3rd fret on the E string. If you were playing a blues based pattern in the key of G you woulld be better to use your middle finger on the 3rd fret as the other notes you'll be using are then easier to reach.
Another appoach to moving up and down the neck involves using your thumb as a pivot gives you access from the 1st to the 7th fret in just one position. Moving your thumb up to the 7th fret then allows you to reach up to the 12th fret and back down to the 5th.
This means that you can access all of the notes up to the 12th fret in only two positions. The video demonstrates the hand shifting technique as well as the thumb pivot option.
