I heard about that, too! Was about to go buy a new broom to test it (Likely wouldnt work for me anyways, my house is on a slight tilt, as we are on a slope) but then there was loads of posts about it being fake.
You have to wait until the vernal equinox, fancy word for the first day of spring. You can stand brooms, pens, even chicken eggs on their ends for about 12 hours that day. My grandmother was great with the eggs. She lines them up along the counters in her kitchen.