Wash bandanas separately by hand or in washing machine on a cold, delicate cycle with your favorite detergent (no bleach). Line dry. After bandana is dried, iron like normal. Bandanas are pre-rinsed and washed before selling.
Resin tags can be rinsed in water, or in soap. Left to dry or dry by hand. Do not leave in direct sunlight or in extreme conditions over a long period of time. Monitor dogs while wearing tags, do not let them chew on the tag.