It is time for me to do a 4 layer pcb, I have experience with 2 layer but I am a 4 layer virgin.
Where should I put the ground layer? Should I have 2 ground layers, 1 below each signal layer?
What kind of trace directionality (if that is a word) should I use for the middle layers?
In eagle are there certain layer numbers I should use for the middle layers?
Will an autorouter do a really good job at 4 layers? I assume that it would do a better job with 4 layers as opposed to 2 layers because it has lots more options.
Tips and pointers are welcome.