You can set the default display styles for all objects
Steps
Tap to activate the tool for which you want to set defaults
Ensure nothing on the canvas is selected
Select the bottom option on the displayed submenu
Notes
Different subsets of these options will appear depending on what you currently have selected.
To change display styles for individual objects already on the canvas click here.
Options can include:
Color
Text Styles
Transparency
Line Weight
Line Type
Measurements
Ability to add arrow heads to line start and end
Wall Colors