If there's any typos or confusing grammar, let me know. I did my best to proofread. >o<
If you have a padded cup, traditionally, the pad goes under the bust to push up the breast. Yoko, however, has what is affectionately known as “underboob”, so if you intend to attempt underboob, you may consider facing the padding in a different direction so that it lays better and doesn’t want to fall under your bust like it is designed to. Mine, for instance, are on the insides, facing each other, as I found this most comfortable.
You may line your pads if you like. I left mine unlined and it has not been a bother to me.
When applying the cord around the neck and on the front, make sure your cord is not twisted and will lay flat when worn.
The reason I don't recommend PVC (especially non stretch) is that because it is not a regular fabric with just fibers, as it is treated with a chemical on top, so once you punch a hole in it with the needle, that hole is not going to recover very well. In other words, if you mess up and have to rip out some stitches, it's probably going to show. On top of that, if it's non stretch, PVC doesn't drape very well. Also note, this is simply how I made my top!
Many people alter plain bikinis or sew their own, but I like the shape and fit of the padded bikini cups as opposed to a flat triangle.
On top of that, it's rather sleek! There is more than one way to cosplay, so be sure to check out some other tutorials if you're needing extra assistance. In the meantime, I'd love to answer any questions you may have.