3D Splines and sweeps for cables

I'm sure there's something, somewhere that can teach me how to do 3D splines to make cables. I know how to make them alright, but I can never get the hang of getting the curves right. I've spend over 14 hours now on a 6" cable and it still doesn't look that good. I move one part, and the spline bends somewhere else. I try to sweep what I think is good and I get a topography error. I'm so glad it's time to go home now, but tomorrow is another day! Why cant I just drag points, otate around my part, drag points,. and just make it?

SolidworksParts And Features