(in blender Cycles) I have created a Sculpt of a head with dynamic Typology, created a retypology. Uv unwrapped the low typology (no mirror modifiers). I then created a 2048 by 2048 new image to bake the normals to. I baked the image and here are my settings everything is smoothed with the generic smooth vertices toggle. I am sure that the normal maps should have better results than this from what i see other people getting on youtube I have put quite a bit of time into walking around in circles on the internet and in blender so help at this point would be very welcome.there is also a weird cuttle fish effect on the faces skin I dont know if that is just a product of the pixels but to me it looks obvious and ugly. I just created this account to ask this question so i am yet to figure out how to post my blend file but hopefully i can solve that one.
First, if it isn't already, set your normal map texture to "non-color data." It doesn't work properly if it is set to color data.
If attaching the normal output to the normal input of the diffuse shader doesn't work, this node setup (courtesy of @david) will invert the normal map.