Hi,
Can you elaborate your question?
I'll try to throw some stuff out to help first.
UG Sketcher by itself cannot really help with design intent.
However, by using datum planes relative to something else, and by incorporating Expressions into your sketch, now you are adding Intended Elements into your sketch's design.
For example: Condsider a tube that follows a path. For arguments sake the path or guide is on a flat plane. My Sketch can be the tube guide path or centerline. Now I can put an expression into the Expressions list to define Bend Radius, Wall Thickness, Tube OD, Length....etc. Now let's say my tube is a connection from one known point to another known point. A-B. And in my assembly I define the distance from A to B. In my tube part I can place two datum planes offset from one another at d=A-B. Again, I can put this in the Expression list to make it easy to define and modify. Now I have a sketch with Design Intent. What is the intent of my part and assembly design?
Sometimes it's helpful to build the part first, any old way you choose, and then as intentions form, go back and add parameters that help define the intent of the design.
Bubbers