One day I was working on a princess seamed garment top and needed to press the seams. While pressing the seam flat to set the stitches, I noticed how the curve of the princess seam closely resembled the pointed curve of my ironing board. Instead of using a tailor's ham, I used the edge of the ironing board and was amazed at the results. The very blunt edge of the ironing board proved to provide a perfect curve for the princess seam.
Here is a photo of how I align the princess seam along the edge (not the top) of the ironing board.
This next photo shows how I use the iron and continuous steam to mold the curve around the edge of the ironing board.
I hover the iron from the top and the front edge of the garment. I don't think I'll ever use a tailor's ham to press princess seams in a bodice again!