Create this beautiful built-in architectural feature by identifying an underutilized section of drywall located directly adjacent to the bath or vanity station. Cut open a clean rectangular recess between two structural wall studs, inserting a curved plywood template header into the top frame to form the precise archway silhouette lines. Line the entire internal cavity with a thick, completely waterproof tile-backer board, sealing the seams meticulously with fiberglass tape and liquid waterproofing compound to ensure zero leaks. Face the internal archway surfaces with soft, hand-thrown ceramic mosaic tiles finished in an ultra-matte sand or chalky white texture. This alcove serves as an ideal platform for organizing plush organic rolled towels and daily bath essentials neatly out of the way.