Creo Interactive Surface Design (Style) > Curves > Creating Curves > Curves from a Surface > To Create a Curve from a Surface
  
To Create a Curve from a Surface
1. Click Style > Curve > Curve from Surface. The Curve from Surface tab opens.
2. Select a curve type:
Free curve—Click , or right-click and choose Free.
Curve on surface—Click , or right-click and choose COS
Isoline curve—Click , or right-click and choose Isoline.
3. To select a location for the curve, perform one of the following actions:
Click a point on the surface for the curve to pass through.
Click the References tab, click the Surface collector, select a surface, and then click a point on the surface.
A curve from surface with a default orientation is created.
4. To switch the curve direction, perform one of the following actions:
Click .
Hold down the CTRL key while you click the surface.
Right-click and choose Flip.
5. To move the curve along the surface, drag the curve, or type a value from 0 to 1 in the Value box.
6. Click .
7. If needed, convert a curve from a surface to another curve type by selecting the curve and performing one of these actions:
Click Style > Curve > Convert.
Right-click and choose Convert.