I would change the fluid every 30,000 miles max using only the OEM fluid - regardless of “lifetime” or some other high interval the manufacturer says.  Also, baby it (don’t drive like a maniac), stick to more highway miles than city miles (less strain), and definitely don’t tow with it.

If you can help it and want to keep a car for as long as possible, avoid CVTs in the first place.

Change the fluid every 30-40k miles. Do not push the car very hard. 

You can destroy any CVT in a minute or two, (see video in comments, there are auto generated and translated subtitles in English) there isn’t any way to make them last consistently.

But generally you want to avoid situations where your engine rpm changes but your speed doesn’t.

any off-roading, or heavy traffic, or racing will almost certainly fry it.

basically what you want to do is drive it gently and change the oil with an oil extractor (on Toyota cars it’s needed, on some models like Kias you don’t need fancy tools) every 20k-30k miles.