Probably the most well-known exoskeleton suit is Iron Man.
In concept, you'll usually see Exoskeleton suits with either tight-fitting joints (perhaps similar to plate armor, I'm not sure), or, you'll see a mess of wires and occasionally gears. One thing that is naturally ignored or not explained well is the weight that such a suit would have. Supposedly, the person inside can lift his leg just fine.
Sometimes this is attributed to light-weight armor - making the suit almost more like high-tech all-encompassing military combat armor.
Other times, the person inside is actually pushing against sensors that trigger the suit to move in the desired way via mechanical motion. Gears, Hydraulics, etc.
My question is strictly covering the second case. However, also keep in mind that there is a human arm and leg in there - I'm not aiming for a pilot who controls the appendages while sitting in a cockpit.
How would the mechanical connections of joints (primarily those on the shoulders, hips, and knees) actually function to power the limbs into the correct positions, while staying somewhat true to a humanoid shape?