Layer

 

1.-Menu draft/administration.
2.-Menu draft/style libraries.
3.-Menu create/style library and here you change the representation color and style.

style library for colour settings, i need same colouwise layers after exporting DWG. format.

AutoDRAFT User Guide / 6.-Drawing Editor - Miscellaneouse Facilities / 6.1.-Layer Mapping

In this document, you have the steps. You have to do a mapping.