Use your legs or provided bicycles, if going further, take an Uber.

Always agree on a price in advance

no need to buy water

Elders will probably not speak, all 50 years minus should speak to some level. I hear often that tourists are surprised how many people actually can speak English and how well they do.

but be careful as a tourist in any city

Prices can go up like crazy

These clubs can scam you (overcharge you), avoid to go there, Split is not a sex tourism city.

I personally am not aware of a single place in Split and Croatia where you cannot take photos

Croatian police are really serious about those

if you are on a bench outside on Riva having a beer its completely fine. If its night and you are with a bunch of your friends drinking outside and singing, still fine (your can get warned to quite down, but that is all). If you are drunk in the middle of the day with drinks in front of the families - its not fine, you probably wont be fined, but you may be removed someplace else by officers

this info is for smokers as well as for non smokers

All other places including restaurants will accept credit cards, but I am not aware of a single bar that does.

Restaurants - eating is a must, no smoking in most of them, seated on the tables Bars - no food of any kind, just drinking, smoking allowed, tables provided but also standing around is ok, no booking needed

I prefer to drive a bike in Split on a pedestrian zone on very busy roads. No strict laws about these. It is fine to use road, but I would say that the regular drivers are not 100% used to see bikes on the road., especially at busy roads.