At the end of March 2017, the new model 124 will come standard with a magnet. Thus, you can wear your tracker without pockets. Furthermore, the tracker's accuracy of measurements will also be improved by using a magnet since then the tracker is prevented from swinging.
As for how to wear the magnet, we strongly suggest following the important tip: don't wear it at the outside of your skirt, dress or trousers. Otherwise, you would probably lose your tracker by this way. Therefore, for performance and security reasons, it's better to put the tracker in your pocket or under your dress. For example, you can pull out your pocket, clip the tracker to the pocket and then put it back in, while without pockets you are likely to put the tracker inside and the magnet outside of the underwear but underneath the dress.