I gots me a couple of plain old tube singlets from the underwear section. they're usually way too long so I cut off a few inches off the bottom and use that to make the ruffles. I don't have an overlocker, so I just strech the strips of fabric as I go and use a tightly spaced zig zag stitch down one side. This creates those wavy looking bits.
then I just sew each ruffle on to the top! probably best to use zig zag for sewing the ruffles to the top too as the singlet needs to stretch over the chest, so the stitch will need to stretch as well.
so I added a little black bow-tie cos I thought it needed something extra, then I added that faux laced look by just cutting little rectangles from a black ribbon (you'll need to burn the ends with a lighter or fire of some sort so it doesn't fray)