Thank you for reaching out to the Ohio State University Extension Ask a Master Gardener Portal. 

To answer your question:

There is just one practical way to improve clay soil: working in plenty of organic matter.

Common sources of organic matter include peat moss, decomposed animal manures and compost made from leaves, plant refuse or grass clippings.

Spread anywhere from a 1- to 4-inch layer of organic matter on the soil and work it into the top 6-10 inches. Remember, organic matter breaks down over time, so it’s best to replace it once a year.

Clay soils aren’t all bad. They hold water and nutrients very well. Clay particles hold onto ammonium and trace elements like potassium, calcium and magnesium. This makes it a fertile soil. All you need to do is break it up a bit so water and air can flow freely.

extension.missouri.edu/g6955

Here is a link with a ton of information about soil and a good resource.  

https://extension.psu.edu/soil-management-in-home-gardens-and-landscapes

I hope this helps.  Please feel free to write back if you have any additional questions.

Thanks again for reaching out. 

Happy gardening!

I can send you information on making your own compost at home.  If you're interested, please let me know.

Thank you!