Before collecting your samples, be sure to activate your kit (visit start.yoxly.com). After you have collected your samples and have ensured the lid(s) on your sample collection tube is secured for shipping, place your sample(s) into the biohazard bag, and seal the bag shut.
Once the biohazard bag is sealed, place it back into the Yoxly kit box and close it. Place the kit box into the pre-paid return envelope provided with your kit.
You can post and return your samples in any Royal Mail postbox (you do not have to post them from an Royal Mail physical branch).