Hey, I rest my thumb on the edge of the pickup. When I hold my right elbow straight up in the air then my fingers are perpendicular to the string. However, after a while of this I get tired and drop my elbow to rest on my bass. When I do this, my fingers aren't perpendicular any more, they slope off the strings at an angle of about 30 degrees. Am I doing something wrong here? I thought fingers were always supposed to be perpendicular.