The tail rotor blows air sideways pushing the helicopter the opposite way - to stop the drift you tilt the main rotor in the opposite direction to the drift with lateral cyclic. When the rolling couple formed by the TR thrust and the horizontal component of MR thrust are balanced by the opposite rolling couple provided by the mass acting through the C of G and the vertical component of MR thrust - then you should be in a hover over the ground with one skid lower than the other. Try putting the 'wings level' in the hover and the helicopter will translate laterally (move sideways).
Once you have that sorted then start thinking that TR thrust never goes away and that 'inherent sideslip' is a fact of life in a single rotor helicopter, you can fly in balance or wings level but not both at the same time.