I think with some newspaper and plastic in your tub and an old 5 gallon plastic bucket. It really doesn't have to be that messy for a single project but I would pull the concrete out of the bag to put it in the bucket outside the door or patio or such until you add a little water and blend. The dust from the concrete until the water is added is my least favorite part.
Make sure your Manager is gone for the day................
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This is another brand new one with a 16 inch wire fan blade cover used at part of the armature... Still is setting and will need to be covered in a large trash bag and misted daily for a couple days
