Where to find a bag
There’s a drunkard who hangs around on steps roughly opposite the Whirling-In-Rags hotel, to the west. He has a bag next to him and he’s in too much of a stupor to stop you from taking it, nor does he seemingly care.
Once you have the bag, equip it in one of your hands on your inventory screen and click on bottles lying around to pick them up. Hold TAB to help you find them.