I've been playing for about 8 months and I can't help but worry that I use wrong technique. All the guides I have read about left hand position say to rest the thumb flat on the back with fingers perpendicular to the fretboard. However when I play I constantly want to position my fingers tilted side ways down the fretboard. When I try to make them perpendicular, I lose a lot of the maneuverability in my hand and I end up not being as accurate. Should I start practicing heavily on keeping my fingers straight or is it okay to do this?

I also have smaller hands and many times when doing power chords, I will unintentionally mute the high e string. When I try to bend my wrist down further for clearance it also kills my maneuverability, especially when moving up the fretboard. Any suggestions are appreciated.
I dont think that there is any way to keep your fingers perfectly perpendicular with the fret board at all times. What techniques would you say you use that cause your hand to tilt?
I notice it tilting as I go down strings, like my hand will be more straight on the 6th string and if I go chromatically down the strings, they will begin to tilt down the neck.
Having your thumb on the side is more comfortable and gives you more power for bends. Placing the thumb on the back of the neck makes for more speed and clarity. So naturally the answer is to learn both positions and when to use each.
Stop whining and learn your theory!

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