Just using a curved line and a circle to represent koru is a good way to start out making your own kowhaiwhai designs.
Start out by drawing a couple of lines as a boundary to keep your design in line. Add notches and filler lines to give the design interest and the 'Maori' feel.
Choose a design to play around with. Repeat your design, flip it, rotate it (yay! for graphic programs)...
... and end up with something like this:
Have a go! Would like to see anything you try or would like to share with the Maori Printable blog readers.