I understand that printing and distributing fliers is an obvious choice for an offline strategy however, especially in the beginning, I am thinking of possible multi-use strategies.
One of such I have mentioned in the chat and that is, what I got to know, in English called beer matt. These are multi-use long-lasting high-exposure if placed in a touristic pubs. And most pubs would just distribute them for free because they tend not to care.
Another multi-use strategy is to use stickers and put them on the maps of underground, buses and trams.