Lick your fingers and slide them along the bottom of your shoe. This is gross but works for a short while. The dampness on the bottom of the shoe makes them stop short on the court.
Purchase a Sticky Mat. Step on it at the beginning of your play time. It removes all dust and dirt from the bottom of the shoes and gives you better traction.
Apply a traction fluid to the bottom of your shoe. Use a towel to wipe it on. This will remove dust and grime from your soles and give you added traction. You will need to clean them again when you feel your shoes start to slip.
Spray the bottom of the shoes with hair spray. This doesn't remove dust from your shoes. It creates a sticky film on the bottom which allows your shoes to grab the floor better and prevents you from sliding.