Paying off karmic debt can be nuanced, but essentially, you must find a way to balance out the karmic energy. This can only be done by identifying the nature of the karma and noticing how it tends to manifest in your physical or internal reality. It can be tricky because we are often blind to our karmic patterns.
However, you can avoid the frustration of being delayed by blind spots when you consult with an expert who specializes in helping others work through karma. Doing so will get you solid direction and provide you with the support to start working through your karmic debt.