If FOLIO is ever offline for an extended time (due to connection issues or during major updates), use the CircBackup app. This desktop application allows you to check out and check in by capturing user and item barcodes. Barcodes are stored within CircBackup. When FOLIO is available again, you can output the file of barcodes and scan into FOLIO.
Best practice for scanning into FOLIO is to check out all materials first. Then discharge all materials - in case users borrowed something and immediately returned it.