The phrase "to cross the straps" means to create an X-shaped pattern with two belts, ropes, or similar objects by passing them over each other. Full definition
Complete with cross straps on the back, and a blue and white striped rope belt. (sophieandtrey.com)
Crafted from soft leather, this slip on design features crossed straps over the foot, a spacious rounded toe and a lightweight, flexible and highly durable sole. (kelkoo.co.uk)
Featuring a tan cross strap design with studded detail, style these with literally anything for a killer look. (prettylittlething.com)