This question has options. How would someone go about accomplishing this goal?
Make a merry go round

Options: 1). Put a large sturdy bar in the ground and set it with concrete. Make a large round platform and attach it so that it has play. attach some sturdy handles and make it safe.; 2). Use a huge saucer sled and put it on a bucket in the yard and push the baby around in circles. If this doesn't work or isn't fast enough, use a desk chair that swivels.;
1).