According to Webster's Dictionary, an "etui" is a small ornamental case. The word is believed to first have appeared in the common English language around the year 1611.
Today, we usually apply the word for a small sewing organizer that has been embellished in some way. Usually, these are rolled or folded and closed with a clasp or ties of some manner. Boxes with lids that have inside pockets and other organizational elements are also in this category; but usually small in size...to be considered "delicate".
Here are some photos of one I finished this morning. Simple, but enjoyable sewing just the same. This specific one is constructed of an Outer Layer which has some embroidery and a hook/eye closure.
It has as an Inner Layer that contains a large pocket, smaller pockets with embroidery accents, and an elastic band.
The large pocket can hold a small pin cushion, also with embroidery, or items that do not fit within the elastic band; such as this little box of straight pins.
The elastic band can secure pins, pencils, seam rippers, stiletto, tweezers, snips, glasses, etc...anything that can be placed under an elastic band.
The embellished pockets are sized to hold a pair of embroidery scissors and a thimble.
Once you decide how large you want the rolled or folded Etui to be (this one is about 6" x 9") then repeat the length for the number of "folds" you want. Add a "flap" to secure a clasp, or omit and add ribbon to tie the finished item.The overall cut size of this one was about 9.75" by 22.00" before sewing any seams.
Select embroidery designs for at least one of the outside sections and some smaller designs for the inside pockets. I selected a wool for the outside fabric, small pockets, and pin cushion; but, cotton or silk would have been wonderful to work with as well. The inside should be reinforced to hold the weight of the pockets. I used fusible fleece for the inside fabric and medium weight knit fusible interfacing on the wool so it would hold it's shape. Recommend you draw your entire Etui out on paper so you can "play around" with the position of pockets, etc. It's a good idea to place the individual tools you might be using down on this paper pattern so you can be assured that the final Etui will actually hold what you need it to secure. Have fun designing and creating your own version!