Many (if not all) novice players struggle a lot when learning the C chord.
They suffer sometimes for weeks to get it sound correctly.
The trick to learn it faster is starting from the A minor chord. The A minor chord is way easier to learn and if you can play that correctly it is just a matter of moving 1 finger to play the C chord.
You only have to move your ringfinger to the A string on fret 3 to get the C chord.
Do not move your other fingers or wrist when replacing your ring finger and make sure your thumb stays straight up.
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NEW !! :
Learning chords - Part 1 - Beginner level
Learning chords - Part 2 - Intermediate level
See also: