Q: Here is a goal: To bend a metal rod precisely to make a hinge.

How would you accomplish this goal?

A: Use pliers to bend the rod.

Q: Here is a goal: How to clap?

How would you accomplish this goal?

A: Beat both palms together rapidly until they produce a simple melody.

Q: Here is a goal: How to perfectly cut the strap of a dress?

How would you accomplish this goal?

A:
A good way to cut would be to carefully cut the strap using a sharp scissor right at the boundary, and the sowing/cutting away any rough patch.