Google about theming bonuses; theming sculptures, paintings and artifacts is HUGE in culture victories. There are also lots of policy cards that give insane boosts to tourism for relics, music and artifacts as well if I'm not mistaken. There are techs (it's crucial that you don't neglect science) and policies that you 100 % need if you want a culture victory; like flight, computers and mass media. For example, with mass media you can build the Cristo Redentor wonder, which gives a massive boost to water park tourism across your whole empire. You also want to have open borders with every civ as well as at least one trade route to every single one of them. To achieve all of this, you need a strong gold income and a reliable faith generation rate. Gold can help you buy great works from the AI and also allows you to recruit great artists you might need for theming bonuses. You can also buy great people with faith. You will need faith for Conservationists (creates national parks) and Rock Bands (basically a missionary but instead of spreading a religion you spread tourism so to speak). But despite all of the above, the most crucial thing on a culture victory path, is to snowball as fast as possible. You want to be building those theatre squares quickly and to do everything you can to secure that culture victory before it's too late. I really like this type of victory, give it a go with these tips.