Step 1: What you need
• Embroidery thread (I used about 12m)
• Flexible cardboard
• Duct tape
• Super glue
• Verbatim TUFF 'N' TINY USB Flash Drive (e.g. on amazon.com)
Then fold the cardboard length wise in half and tape it close with the duck tape, but remember to leave the ends open, as shown in the first image. Cut one end open, put duct tape on the inside and tape it back close. This side is going to be your cap so make sure that it fits without sliding out. Now peel the casing of the flash drive off. To smoothen the edges of it (else the end can be seen through the bracelet) fold a piece of cardboard and use the super glue to glue it to the flash drive. Leave enough space as shown in the third picture to make sure that you get a tight fit. Glue the flash drive to the inside of your tube and make sure that it closes, without leaving a gap.