To construct the 1-up chair:
*paint your design on the tub & top it with a clear finish.
*Cut your 54" square into a 54" circle.
*Cut out 5 felt circles (or whatever details fit your design)
*Top stitch your felt details onto the large fleece circle
*Fold over about a 1 inch hem and sew the edge around the entire circle leaving about a 1 inch opening for the elastic.
*Thread your elastic through the opening completely around the circle.
*Sew together the ends of the elastic to secure them.
*Sew shut the 1" opening (optional)
*Fill the base & mushroom top with your soft stuffing material & the base with your storage stuff.
OPTIONAL: Fill just the top and add the garbage can lid as a divider if you are storing irregular shaped things or leaving the bottom empty.
*Flip the top onto the base and pull the elastic down around the rim of the tub.
I designed it this way so that the filling is easily replaceable and accessed, and so the chair is dually purposed.
*The koopa shell ottoman is done by using these same techniques on a rectangular storage tote.