Select the top layer, then select copper area, as shown below.
Draw a square around your board outline and then set the net to the net you want that plane to be. Repeat the process for the bottom layer.
OK. Thank you.
Should I do that before or after I use autorouter?
What is the difference than using this menu:
Hi
You can refer at the dialog right-bottom corner icon.
via: [https://docs.easyeda.com/en/PCB/Layer-Manager/index.html#Layer-Manager](https://docs.easyeda.com/en/PCB/Layer-Manager/index.html#Layer-Manager)
when the inner layer type is plane, you can create the plane directly and divide the plane area by the track.
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