How do you save for non-monthly fixed costs?

Hi guys, how do you keep track of your finances? It sounds like a stupid question at first, but here's some more context: I've been through a few different things. I had an Excel for several years, but since my partner added joint expenses it became very tedious. Finanzguru is of course the big player on the market. But they are becoming more and more like brokers and more confusing. I also don't have any cash when I go to my favorite kebab shop or for drinks