Hard to determine how to advise you since you didn't say whether you're using KB/M or gamepad. With KB/M it's as follows:
If you're talking about the part where you have to electify the batarang to blow the fuse box, all you need do is let the batarang fly into the arcing electricity, then make a U-Turn with it (LMB+RMB) and steer it all the way around to it.
Other than that, you open the gate to get to the elevator via either tossing the batarang through the whole in the fence by the left fence door, or up over the area where Penguin stood, then arc it left down the stairs. Mouse movement steers it.
Don't forget to brake the batarang where needed when making tight turns and/or zeroing in on a target (RMB).