[Love Live PDP] Kasumi Diamond Cosplay Tutorial

This is a supplement write-up to the video tutorial below. I wasn’t able to get a lot of photos of the WIP so mainly using screenshots in this post. Here’s where you can purchase the 3D prints. If the link has died, please DM me on Instagram.


I usually start off my design with a sketch that contains some information on what I’ll be doing. In the notes section I’ve written down the commission information (size, payment, requests, etc).

This is the pattern I ended up with. It’s not perfect so I’ll be altering them as I go on based on my mannequin.

The bodice was altered from McCall’s pattern M69563. I used the existing sweetheart pattern but made a new panel for the lower portion.

The skirt is just a simple full circle skirt that ends up above the knees.

The bolero used Simplicity 8061. I cropped it to come below the chest, and added a curve from the neck to the side. The sleeve was altered to have a puffy sleeve.

The hat used 2 circles, where the 2nd one had the center cut out.


I serged all the patterns together and tested it on the mannequin before straight stitching it. I used plastic boning to give it some support on its own. A zipper was added in the back.

Decorations such as lace and ruffles were added last. I used a 3/4″ and 5/8″ metallic gold ribbons, 5/8″ white satin ribbon, and 1.5″ yellow ruffle lace trim.

For the neck, I used a 5/8″ yellow double sided satin ribbon and used superglue to attach the 3D prints together.


The skirt was just a simple circle skirt, I later cut the left lower portion to make it more asymmetrical

I added a 1inch elastic waistband. Then added the yellow ruffles (which were hand pleated), 7/8″ gold ribbon as a bias tape replacement, and 4″ green eyelet trim. Please know how much fabric you have as this took a lot of fabric than I was expecting.


First sew the body pieces together. Loosely stitch the upper and lower portion of the sleeve and pull the thread to create puffed sleeve. Then stitch on the sleeve to the body.

Various sized ribbons were used for the edges. I couldn’t find my white pleated trim, so created my own with 1.5″ white satin ribbon.

A button snap was sewed on as a closure, and a ribbon bow was added on top of it.


First, the top and bottom fabrics were added together. Using poster paper and tape, I made an insert so the hat will stand up on its own.

1.5″ green ribbon with a 7/8″ white ribbon band, were hot glued on the the edge of the hat.

The folding ribbon decoration was made by attaching two ribbons together, then gluing down each fold for the two-toned look. I used ostrich feathers for the feathers.


All the 3D prints were primed, then colored gold using Rust-Oleum gold spray paint. (Purchase Link) The hair clip was attached to a mini alligator clip.

For the wristband, I hot glued down two yellow ruffle trims together, then added a green ribbon in the center. A button snap was sewn later.

For the leg warmers, I used some scrap yellow fabric and added a 1/2″ elastic to the end. Then I double layered it and hot glued them together while adding pleats.

I made a design outline with scrap fabric and paper for the side ribbon. I attached yellow and green fabrics together using basting spray. Since this adhesive can detach I used hot glue to seal all the edges in. (You can use spray adhesive too, but I had some problems with over saturation in the past) The rhinestone and center bow was then glued on.

This is how the entire cosplay looks in the end. If you can please donate to my Ko-fi, it helps me out a lot.

Thank you for reading!