Starting with the hip and working outwards, scale and rotate all bones until the whole biped is as central to the mesh as can be. As a guideline, the size of the hip and spine links should be approximately two-thirds the size of the mesh.
Be sure to utilise all viewports - just becuase the biped is aligned in one viewport, doesn't mean that it is alligned in others.
Take your time over this, as it will save you hours when applying physique in the next step. This is a good exercise if you are not familiar with 3DSMax.
Remember to keep figure mode on!
