Your bandwidth requirmrnt would decide the gm for the input pair.
Also the slew rate requirment would decide the bias current through the tail current source.
Once we have the 2 we could start with the design.
You choose the architecture depending on what is your input range and PSR requirment.
Take care of the current you are going to need for active loads. Read holberg to get idea on that.
The active load architecture could be choosen on your output swing requirment.
Once u have all the W and L you would know the capacitance at non-dominat pole locations. U could get an idea on your pole locations and a phase margin.
Hope it helps