Originally Posted by: jovantaewanderwayI am struggling with keeping my pinky positioned on the 4th fret all the time as I am doing the spider walk exercise or when experimenting with the pentatonic scale.[/quote][p]It's fine to use your ring finger when necessary. You can get your pinky into the act by playing spider fingers or pentatonic scales in a higher register, further up the fretboard where the frets are closer together!
[quote=jovantaewanderway]I am aware that its great to use the pinky, but is it acceptable to bounce and move the hand a bit when playing notes back and forth from index finger to pinky or should they be stationary?
Yes, good observation! I do that frequently when playing wide stretches in lower frets. It can actually help you develop a lighter more mobile touch. This is because there's no reason to squeeze the lower frets as hard once a higher note is fretted on the same string. So, you can let go of it, slightly slide your hand up to reach the next notes.
I also have these tutorials aimed at improving strength & dexterity.
Building Pinky Strength & Dexterity
https://www.guitartricks.com/tutorial.php?input=1292
Trill Drills
https://www.guitartricks.com/tutorial.php?input=1829
Hope that helps!