Most dishwashers have a cylindrical or flat filter at the bottom. Twist it counterclockwise and lift it out. Check your manual for exact location.
Scoop out water from the bottom of the dishwasher using a cup. A wet/dry vacuum works best for quick removal. clean drain dishwasher
Replace the filter and rack. Run a short hot-water cycle with no detergent to flush out loosened debris. Most dishwashers have a cylindrical or flat filter