Step 1 :The sine function gives the y-coordinate of the point on the unit circle that is an angle of \(\theta\) degrees counterclockwise from the positive x-axis.
Step 2 :The sine function is -1 at \(\theta = 270^{\circ}\).
Step 3 :So, the solution to the equation \(\sin \theta = -1\) is \(\theta = 270^{\circ}\).
Step 4 :\(\boxed{270}\) is the final answer.