Mark Where the Radius Detail Will Go
Before cutting the sides for the tote, measure the 1x12 to twice the length of each side. Then cut it at the long measurement. Mark the halfway point on this long piece, both lengthwise and across its width. Use a compass to mark a circle around that halfway point. The size isn't critical, but it should be proportional to the width of the board. Draw a line across the board directly through the center of the circle. Make sure the line is square to the edges of the board.