I've created a tutorial on how to make the petticoat in GosuRori #7. Basically, I used their measurements and wrote my own explanation. The measurements are listed as four sizes S, M, L and LL, in that order. If you need to find out what size you are, please consult the Guide to the GosuRori which is located in the memories. For this project you will need taffeta (S - 1m10cm, M - 1m20cm, L - 1m20cm, LL - 1m30cm) and tulle (S - 2m10cm, M - 2m20cm, L - 2m40cm, LL - 2m60cm). You will also need elastic for the waistband. The GosuRori recommends a piece of elastic that is 8.5mm wide. The length of elastic needed can be found below.
Also, keep in mind that you will be drafting your own pattern piece. Here we go.
when drafting the pattern piece, all measurements should be in cm, not mm. that was a goof on my part. i'll take all of your guys' suggestions and spruce this up a bit and post it again, if you want.
While there is no picture of the final project, I do include a picture of the petticoat being worn under a skirt. I hope to add a picture of the final project soon. Since it's my first tutorial, I hope that you guys can give me helpful pointers as to how to improve upon this. Enjoy!