for three finger approach, finger it the same way you finger your D major chord, or a D7 chord,except your fingers are crammed together. whether you use three, one as a bar or two (one as a bar and one as a single note placement, which is referred to as a partial bar chord). I switch between the three options depending on what I am playing. Don't worry, things that are difficult now will become easier, and new challenges will present themselves. As far as the guitar, like others have said, the action on the strings can be an issue. Also remember you're using your fingers, hand, and wrist in a way that you haven't before so it will take a while for those muscles to develop. If you bought the guitar new for one hundred dollars, the guitar could possibly be part of the issue. Terra most of us had these challenges in the early stages of our playing, at one time Eddie Van Halen was a beginner.
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