Not all rib fractures are apparent, it can look only like a bruised intercostal area. In most of the cases even the small tension of the intercostal muscles (e.g. sneezing, coughing) can cause uncomfortable pain. The tape can reduce the discomfort.
Tape the painful place when putting your arms up.
Place the second tape vertically to the first tape.
To finish, place two stripes of the tape vertically when stretching it to the sides. These tapes should support the broken rib.