This puzzle has two sheets. If you look closely, there's already a hydrogen bond -- a blue-and-white "candy cane" -- between the sheets.
Madde's "Sheets Together" video
Loci's "Sheets Together" video
If you drag the sheets closer together, you'll see more hydrogen bonds form between the sheets. If you drag the sheets too close, you'll get clashes.
Shake and wiggle to finish the puzzle.
Technical stuff: a sheet by itself doesn't do too much good. A single sheet is sometimes called a "strand", which may tell you something. When sheets are bonded together edge-to-edge like this, they help to stabilize the protein.