Who says you need concrete to do something on your unicycle.
Try this:
1.) Find a nice quiet office doorway. I hope you dress office casual and you wear some casual tennis shoes. Get on your unicycle and hold onto the door way. Practice idling.
2.) Too easy? Okay…lift up one foot and put it on the unicycle frame. Do one foot idling.
3.) Child’s play? Okay…stand up on the pedals and let the saddle swing down and drop to the ground. With your knee’s slightly bent, stay on the pedals as long as you can. (warning: possible torn work pants may result if you should drop down into the pedals).