A Pinafore
Every pattern I have made calls for the 5 chains (skipping whichever amount they say) for the underarms. I am working on one now that is a size 7, and the larges pattern I found was for 6, so am using that guesstament for the underarms…9 chains in this instance. I think if you are making a odd size, you can pin the shells at a particular place where you think the arms/shoulders look good, and chain anywhere from 5 to whatever (or even 3 I guess if you are making a very small one). This particular dress isn’t rocket science.
One pattern I looked at had some increases, but I didn’t need to on this one. The one following I am having to increase as the yarn isn’t as flowing or as stretchy, so looks too straight up and down.
The Bernal instructions are a bit off…not carefully written. I assume you can still get it from their site, where they use their Mosaic yarn.