I personally use :R1: when I take my freekicks, while holding up for added power. I aim inbetween 2 of the heads in the wall, and then bend with the D-Pad which ever way I want. From about 26-18 meters I fill the power bar a litte over or exactlly half way.
As for the exaggerated effect, that might be because of you using the R3 stick to bend the ball, which I don't suggest you use.