How can I measure 3/4 cup with 1 cup?

Fill a cup with the thing you want to measure. Pour or take out half of it into another cup(this is 1/2 cup,). Now from either of the cups take out half of the thing you are measuring(it is 1/4 cup) . Add this one fourth quantity to half of the quantity now the final quantity in the cup is 3/4( 1/2 +1/4).