Construct an angle of measurement $30^{\circ}$.

(N/A) Steps of construction:
$(1)$ Draw any ray $AB$. With centre $A$ and any radius,draw an arc to intersect $AB$ at $X$.
$(2)$ With centre $X$ and the same radius [as in step $(1)$],draw an arc to intersect the previous arc at $Y$. Draw ray $AY$. Then,$\angle YAB = 60^{\circ}$.
$(3)$ Draw ray $AT$,the bisector of $\angle YAB$.
Thus,$\angle TAB$ is the required angle of $30^{\circ}$.