Why is my shower mouldy
Mould needs food and moisture to grow, so if your shower is getting mouldy down in the corners and edges of your shower then you need to ensure it is cleaned down in these areas. Often people clean the shower by cleaning the shower screen and removing soap scum and maybe wiping or using a squeegee. But the corners and edges are often over looked, use a bathroom cleaner that has a disenfectant or sanitiser and use a brush to get into the corners and edges.
The other very important thing you can do is dry your shower. Almost all shower cubicles that have a door and only a small area above head height to allow any ventilation will just not dry out between showers.
One of the best things you could do is leave your shower door open during the day to allow the shower to dry, also when you are about to wash the towels, use these towels to give a quick wipe around to remove as much water as you can before sending them to the laundry.
If your shower is dry then no mould can grow!