What for does cigar need a bow?
Maybe somebody considers multicolored cotton bow on cigar a decoration. Let it be so. But, first of all it is a label - cigar brand, its' trade mark. Although, there is a version according to which this bow was invented in order tobacco not soil smoker's fingers, moreover if it is woman in white gloves. But according to another assumption, the initial purpose of the bow was to protect the cover from unrolling. But these explanations don't seem to be convincing. You should try a lot to soil fingers of cigar and a good cigar is made in such a way that it cannot unroll even without a bow. It is most likely that right are those who refer bow appearance with Cuban manufacturers that have distinguished in such a way their products from many falsifications with which Europe was full in XX th century.
Some people when starting to smoke leave the bow on cigar, other consider it immoral considering it the same like walking with label on jacket or dress. These two approaches are called North American and British.
Davidoff Company advise not to touch their brand-ring on cigars as it lies down very closely to its leaf and you can damage cigar cover while trying to move the bow. In Zino cigars' catalogue is also told that it is better to leave the bow on cigar at least till you will not smoke it on one third.
Anyway, you should be more careful. If you will touch the leaf it can unroll and you will not be able to smoke cigar easily. If the bow is stuck to cigar it is better not to touch it at all.