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With a stacked MOS transistors you must take care only to the fact that all transistors must be in saturation (for example if they are used like a current mirror).
For example for a Nmos structure:
Start with the one from bellow. The one that is connected directly to GND.
Choose L,W,Vds (base on the noise/matching/current). After that go to the other transistor.
Choose again the L, W and Vds. From equation you will obtain the gate voltage. Because usualy the bulk of the second transistor is connected to the same bulk of the first transistor you will notice that Vds is different for the same size.
And repeate the same procedure for the 3rd transistor.
If this structure is a curent mirror you should set the noise/matching with 1st transistor. The other transistor that is on top of that is used just for Rout increase by aprox (1+gm2*Ro2). So for the second transistor you can use a bigger W/L ratio. This will improve your output voltage range.