Remove grill grates or plates that cover the burner stove, then disconnect the burner and remove the tubes from the gas line. It's important to remove the propane fuel source to ensure that there won't be any accidental lighting during the cleaning process.
Fill a gallon bucket with warm water. Add 2 tbsp. of liquid dish soap and 1/2 gallon of hot water to a second bucket.
Saturate a clean cloth with hot soapy water. Scrub each burner with the soapy cloth until the residue comes off. Clean the connector tubes.
Rinse the dirty cloth in the bucket of warm water and wipe the soap and excess water off each burner. If any residue remains, scrub it with a wet scrubbing pad and wipe it off. Wipe each burner and the connector tubes with a clean, dry cloth.
Scrub any rust spots with sandpaper and a wire brush. Keep going until all traces of rust are removed. Wipe the burners down with dry cloths to prevent rust from forming.