Remove everything inside - Remove floor - Jack up shed - Place large pvc pipe on one side - Repeat and place large pvc pipe of same size on other side - Roll in direction you need - Remove and replace pvc pipe as shed moves. Since you want it sideways you may be able to put pipe under it and pivot it.

If you're using a shed sled or rollers, you'll need to lift the shed with the floor jack to get the moving apparatus underneath it. If the floor jack doesn't fit under the shed, dig into the soil underneath until it does. Use scrap wood as cribbing to stabilize the shed as you lift at each corner.