For this glitch you need to make sure your park is wide for the sheet, it needs a lot of space. Take the rail tool and make a small rail. Now grab one end of it and drag it really far out. Eventually it will turn red, you know your getting close. Then the rail will break off from the support. When that happens slowly bring it back till it connects. Then very slowly drag it away again and right before it breaks off you will notice a big red sheet. Once you have the red sheet like in pic#3, just press up or down on the d-pad. You can either lower or raise the supports to create a big tall sheet or a wide flat sheet.
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