If the second sketch does not exist then you are looking for:
Sketches.AddByTearOff method
If the second sketch exists, i guess that you have to add the profile elements in the first sketch to the part SelectSet:
'These lines are by heart. They might have a mistake. Sorry, no time for more right now.
oCircle2D=oPart.Sketches.Item(1).Profiles.Item(1).Circles2d.Item(1) 'First Circle in first profile in first sketch.
oMySelectSet=oPart.SelectSet
oMySelectSet.Add oCircle2D
oMySelectSet.Copy
oPart.Sketches.Item(2).Profiles.Item(1).Paste 'if there is an existing Profile in sketch 2 or
oMyProfile=oPart.Sketches.Item(2).Profiles.Add(oRefPlane) 'Create a new profile in sketch 2.
oMyProfile.Paste
oMyProfile.End (condition) 'See help |