with nothing selected, click the outline tool on the tool box. Choose your default setting for outline thickness, type, color, etc. and hit apply/ok. a new menu will pop up. select what attributes you want this outline to apply as default.
Form now on this will be your default until you change it.
NOTE make sure you "Save Settings as Default" to do this go to TOOLS/ Save Settings as Default. if you skip this step the next time you open DRAW it will revert back to previous settings
doink I mis read your original post. what you are wanting is not editable. that is the live preview and always works that way