Of course you can introduce it any way you like but this is how we did it.
We simply left the walker in Otis's room from around nine months. He started investigating. Reaching. Climbing. Then pushing it around on his knees.
Then one day wow. Up he goes. He's not walking, he's running. As fast as he can until he crashes into the wall or furniture.
We sometimes move the walker into other rooms but generally only those that have carpet. It also works well outside on our lawn. Once he has some experience we will move it into our other living areas like those with tiles.
The reason we like this style of walker is that he can use it when he is ready and he can use it completely independently.