Check below images and you will know what size you need to tell us :

how-to-measure-swimming-pool-size

 

Just tell us below size : 

                       Water dimension:                inch

                 Pool deck dimension:               inch
A: Deck edge to pool top edge:               inch
C: Deck edge to pool bottom edge:       inch
B: Deck edge to pool right edge:           inch
D: Deck edge to pool left edge:              inch