To Create a Curve on Surface (COS) by Intersect
Use the 
COS by Intersect tool to create a curve on surface by intersecting a surface, body, or quilt with one or more surfaces, datum planes, bodies, or quilts.
COS by Intersect tool to create a curve on surface by intersecting a surface, body, or quilt with one or more surfaces, datum planes, bodies, or quilts.1. Click 
Style > COS by Intersect. The COS by Intersect tab opens.
Style > COS by Intersect. The COS by Intersect tab opens.2. Click the 
First set collector, and then select one or more surfaces, bodies, or quilts. This selection forms the first set to intersect.
First set collector, and then select one or more surfaces, bodies, or quilts. This selection forms the first set to intersect. | The surfaces can either be internal or external to Style. |
3. Click the Second set collector, and then select one or more surfaces, intent surfaces, datum planes, bodies, or quilts. This selection forms the second set to intersect.
Second set collector, and then select one or more surfaces, intent surfaces, datum planes, bodies, or quilts. This selection forms the second set to intersect.4. Click 
OK.
OK.