Choose the panel colour that best matches your design, the size of the unit, and whether you want the headside on the left or the right. Then, choose where the bath is going to go - in a recess, in a corner, or against a wall. Finally, choose whether you want your walk-in bath to come with a plinth, or for maximum ease of access, it can be flush to floor.
Don't worry if you're not sure what any of these options mean. The image of the bath will change automatically whenever you choose a new feature, so you'll always know exactly what you're getting.