Buy a bag of cement mix at a local hardware store/ lumber company if one doesnt have own property to do this on. (It is ok to do this on your own property but anothers and get caught could cause legal problems )
Get a wheelbarrow mix the cement with water, pour into some sort of mold and make your own designs, (remember to thoroughly wash out the wheelbarrow afterwards and all utensils used or more than your project will have hardened cement. This is actually kinda fun and you can be extremely creative with it.