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Use a mild detergent and wash on the gentle cycle. Cut 2 pieces from your fabric that measure 10 inches (25.4 cm) long and 1.5 inches (3.8 cm) wide. The elastic should be cut to 9 inches (22.9 cm). Cut 2 pieces of corresponding Velcro to measure approximately 1⁄2 inch (1.3 cm) by 1⁄2 inch (1.3 cm).

Summary:
Pre-wash the fabric before beginning the project. Begin by cutting all of the items to appropriate lengths.