You have Google? It is right here

https://www.youtube.com/watch?v=F4S_YlzSqt4

This is not a beginner, DIY in any form

You DO need a base. You do need drainage. Whether concrete, crushed stone, asphalt . It isn't just put down some rubber.

Frankly, children have survived on grass playgrounds for centuries : ) Swings,slides, and all manner.

It's a lot of complicated install - and I would contact a pool/landscape company in your area. I doubt the expense will be worth it. Children grow very very quickly and survive a lot of hard knocks doing it

I would just do fake grass not some permanent install that will stink in the heat BTW as rubber always does. IMO the kids out drow the play set and you are stuck with amess.

Over-protective parents are one of the reasons we have cancel culture particularly on college campuses, according to Greg Lukianoff in his latest book The Cancelling of the American Mind.

Children need to be able to associate their bloody knee with having jumped out of the swing too early. Your boss isn't going to put any rubber down for you to get a soft landing when you screw up. The earlier you learn this, the better.

Woah woah woah, where is this over protective BS coming from? I never mention a single thing about worrying about my kids’ safety. I mean, yeah I care about my kids’ safety as a responsible parent should, but not to that “overprotective” sense that you and another above commenter are coming from.

I’m coming from a purely aesthetic and utilitarian purpose. My local park has this flooring and I like it. I need a level and firm, yet soft play surface for my daughter’s ride-on train’s tracks so I can leave them out and not have to disassemble and pack them away every time she wants to play on it. Aesthetically, it would be useful to help define the play area of the backyard and add colorful playful design that my kids would enjoy.

Not to mention, that if you’re worried about my kids not learning from a scraped knee, the surface has a very asphalt like texture to it. It won’t stop from a scraped knee. The give in the surface is also pretty subtle, so it won’t even prevent a broken bone.

I used to work for KaBoom! which is a national nonprofit that builds playgrounds. The only reason to use poured in place rubber is to build an accessible playground. unless you need true accessibility, I would recommend mulch at a depth of 12 inches for a backyard play space: https://kaboom.org/resources/build-playground-toolkit/safety/planning-and-safety-basics

I researched this for our smallish HOA several years ago. It was rejected not just because of the expense, but also because of the issue of repair when it gets messed up. It’s a patch not a seamless invisible repair. We decided on rubber mulch which has served us well. Not the garden variety rubber mulch from the big box store, this stuff was also a big expense. BTW odor has never been an issue here in inland California where it gets blisteringly hot.

There are rubber pavers that we have used and they work great. Easy DIY, just lay them down on the ground. Recycled tire were the type we got from the big box store...easy to load and unload.

Also, falling on rubber hurts…very easy to skin knees and it also gets very hot.