All Bandanas are to be worn over the dogs collar. The Length should be less than the length of the dogs collar and the opening width slightly larger than the widest part of the dogs collar. As a general rule the sizes follow the sizing of our collars e.g. the small will fit on our small collars, the medium will fit on our medium collars etc. However, with the Extra Small and Small you can choose depending on the drop you would like and with the Large and Extra Large you can also choose depending on the length of the drop you would like. Size Guide: Size Length Opening Width Drop Extra Small 13cm 3.5cm 10cm Small 16cm 3.5cm 13cm Medium 21cm 5cm 15cm Large 25cm 6cm 20cm Extra Large 35cm 6cm 26cm Please reference our care page for how to look after this product. All of our products are handmade so please allow for variation in pattern placement and slight variation in size.