The only catch is that you shouldn’t use freshly baked bread. The moisture in fresh bread won't allow it to break into crumbs.
If your bread is soft: tear it into small chunks and place into your food processor fitted with the “S” blade. Pulse for a few seconds at a time until your crumbs are the size you want.
Spread the bread crumbs on a cookie sheet, cover with your favorite adorable tea towel and let them sit out overnight or until they’re completely dry and crunchy.
break it into chunks (if you can) and place into your food processor fitted with the “S” blade. Whirl it in your food processor for 30 seconds at a time until the chunks break down.
Now that your bread crumbs are ready, you'll need to store them in something air tight so they don't get stale.