I bought the Coco pattern the day it came out, and I bought three striped pontes from Girl Charlee the same day, and, of course, waited a few more months before actually making one. I really wish I'd made Coco sooner seeing as how it is the perfect transitional dress.
My muslin was a straight size 7, but what I ended up with here is a straight size 6. Remember that knits, even pontes, have some stretch in them. I went back after this version though and took the skirt A-line down to a size 5 to reduce it a bit.
This green version is a size 6 but tapered to a size 5 to reduce that hem curve. I also reduced the sleeved to 3/4 length. I thought the long sleeves bordered on nightgown, but I'm not sure. I also added the collar with the stripes running vertically. I might eventually add in the length I removed.
I used my machine zigzag stitch on .5 width, 2.5 length as suggested by Alyson Clair in The Colette Guide to Sewing Knits and it worked beautifully. I would recommend samples with various needles and stitches anytime you're working with a knit. I used a 2.5/2.5 zigzag for the sleeve and skirt hems per Tilly's instructions.
The instructions have you stay-stitch the neckline, then apply some stay tape when you hem, which I liked. In the future, I'll go ahead and fuse the knit stay tape to the neckline, sleeve hem and skirt hem before construction since it's easier than applying it in the round. I also added knit fusible to the collar but it literally had no give when I attached it to the neckline, so I might omit that next time.
I used kelly green Toldi-Lock thread from JoAnn based on Alyson Clair's recommendations. I had never considered why you might need to use finer thread with knits, but it makes sense.
Both of these fit on 2 yards of ponte fabric from Girl Charlee. I folded both selvedges to meet in the middle to conserve fabric. I prefer to do this if able since most knit garments have both front and back cut on the fold.
These pontes are a blend of cotton/poly/spandex so they breath a bit better. I have this fabric in royal blue as well to make a third Coco, probably 2/4 sleeves without the collar.
Pattern: Coco by Tilly and the Buttons PDF
Size: 6, 5 from waist to hem
Fabric: Striped ponte from Girl Charlee 2 yds
Thread: Gutermann Mara 100 & Toldi-Loc
Needle: Organ 90/14 Ballpoint
Stitch: Machine zigzag .5 width/2.5 length
Notions: Fusible tricot knit from Wawak cut into strips, stay tape