1. Wade In The Water
Learn in all positions

2. Start in 5th position.

8. Learn in all position Learn this in each of the positions.
Later learn it in all positions in all keys.
Even one song learned this way will really help your knowledge of the guitar and relationships between notes!!
Use this as a starting point for solo work.
Remember to put vibrato on notes.
Also bend and slide up to or down to notes. This can add interest.
Try to harmonize the melody. Play a melody up a 3rd or down a 3rd.

10. Try Harmonizing in each position
Start with 3rds then try 6ths both above and below.
Then try other intervals just to see how they sound.
You could do 5ths with an octave.

13. Analysis of harmony
This song really has only 2 chords to it a Am and a G chord.
So some of the keys that have those 2 chords are:
Am (relative minor to C major).
A Dorian which relates to the G major scale.
My analysis points to either one as being valid.
Therefore you could use either of those scales in this song.
The melody is totally in the A Minor Pentatonic form with the exception of the G# passing tone at the end of the song.
That would be the place to start.

14. Here is a process for you
Learn the melody and chords in one position.
Move to the other positions for the melody and if possible the chords.
Learn the scales to the song in each position.
Start to solo using the melody as the basis for the song.
Later harmonize the song. Try to play in as many different ways as you can.
You might want to try something adventuresome.
For example with this song being in Am. Play the melody on the 4th string and keep the 5th string open as a lower pedal point.
Experiment around and you will discover all sorts of things to do to the song.
You can vamp it using the A as a pedal. This can be very cool.