Altium : Changing PCB Dimention

[raviani]

Hi, I need to make a 15cmx20cm PCB using Altium but I don't know how to change the board size. I tried Design >> Board Shape >> Define from selected objects but I don't know what sould I do next. And how to change the dimention into cm? Thank you so much.

 

[Kick]

For board shape: Draw board outline (15cm and 20cm) in Mechanical layer using Line. Next step is select these outline. Go to Design >> Board Shape >> Define from selected objects.