problem on dimesioning the board from the board origin?

Hi.

For my pcb board i want to check the dimensions. For that i had tried datum dimension from the  board origin. but when i click from the origin the dimension get enabled in the larger font size. I am trying to reduce the corresponding size of it.

Before dimensions i had done the drafting parameters option and  gave ANSI standard/ Millimeters units.Give anyone provide the proper settings to the drafting parameters option.

After that i had done the dimension means,what type for the dimension have to been used.unit are in mm.


Thanks & Regards
Dhamodharan