16 October 2023

Fitting the Sonny jacket

Fitting the Sonny Jacket

If you're thinking of making the Sonny jacket and have a few questions about how to get a great fit, you've come to the right place.

Sonny is an ultra-versatile jacket with a relaxed, boxy fit, making it simple to fit. Good stuff! However, as we are all wonderfully unique in shape and size, you might want to make a few changes to your pattern pieces to make it suit your body better. Here, I'm going to talk you through the most common fitting adjustments you might want to consider making to your Sonny jacket. 

In this post we're going to cover: 

  • Making a toile 
  • Choosing your size 
  • Lengthening or shortening pattern pieces 
  • How to combine pattern sizes 

Making a toile

A toile - or a "muslin"- is an initial mock-up of your garment in fabric you don't mind using for testing purposes. A toile is a great opportunity to test the fit of a sewing pattern or practice a technique, like inserting a collar, before you cut into your nice fabric. 

The Sonny jacket is a relaxed fit, meaning you don't necessarily need to make a toile for fitting purposes. If you're planning on wearing your favourite chunky knit under your Sonny and want to check it will be comfortable, we recommend making a quick toile of the front and back bodice pieces and sleeves to check the fit. Pick a fabric with a similar weight and drape to the fabric you have in mind for your final project. 

We have a comprehensive blog post about toile making. Go check it out if you want to find out more!

Body form with bust, waist and hip areas highlighted

Choosing your size

11 October 2023

NEW! Meet the Sonny jacket and lining add-on patterns

Tilly and the Buttons Sonny Jacket sewing pattern in sizes UK 6-34

Sewists, are you ready to meet the jacket of your dreams? We're thrilled to introduce you to the Sonny jacket sewing pattern and the Sonny lining add-on pattern!

Ultra versatile, you can make it as a classic jacket that will never go out of style, or try the on-trend prairie collar for Ganni-esque vibes. Sonny can be made as a casual unlined jacket, but if you do want to line it, we have created a separate lining add-on PDF pattern for a polished inside finish. 

Read on to find out more about Sonny...


Plus size model wearing corduroy jacket made using Sonny jacket sewing pattern
Model wearing a lined denim jacket with oversized prairie collar - made using the Sonny jacket pattern

Technical drawing for Sonny jacket pattern - Tilly and the Buttons


One of the things we love the best about Sonny is how different it can look depending on which version you make and what fabric you use. You can go utility style with a classic pointed collar, or make a designer-style jacket with the on-trend frill prairie collar. Let's take a look at Sonny's details:

  • Boxy fit bodice with drop shoulders and princess seams creating gentle shaping at the bust 
  • Choice of pointed collar or oversized frill collar 
  • Separate yokes, forward shoulder seams and front panels 
  • Optional chest pockets and flaps 
  • Easy-to-sew straight sleeves 
  • Choice of hip-length or cropped hemlines 
  • Mock flat felled seams create a durable finish
The Sonny lining add-on pattern includes bodice and sleeve lining pattern pieces to compliment all versions of the Sonny jacket, as well as a hanging loop so you can display your gorgeous creation with pride.  

Plus size model wearing corduory jacket made from Sonny jacket patternBack view of plus size model wearing corduroy jacket - made using Sonny jacket sewing pattern


Both the Sonny jacket and lining are available in sizes UK 6-34 / US 2-30 / EUR 34-62. The full size range is included in each pattern. Sizes UK 6-16 and 18-34 are created and graded for a different set of proportions, so you will notice there is more shaping on the larger pattern sizes to account for a fuller bust.

The Sonny jacket pattern is available either printed or PDF, and the lining add-on is available as a PDF download only

Order the Sonny jacket printed sewing pattern and we'll send you a beautiful package in the post, with a full-colour instruction booklet. Made in the UK, our patterns are printed on durable paper which you can use again and again without it tearing or scrunching up. 

The Sonny lining add-on pattern and Sonny jacket are available as an instant PDF download. You'll get an email straight after purchase with a PDF to either print and assemble at home on A4 or Letter size paper or send to a copyshop or pattern printer to print full scale on A0. Need further help? Read our guide to using PDFs.

Whichever format you choose, the pattern will be accompanied by our award-winning instructions with step-by-step colour photos to guide you through the project. The pattern pieces themselves are clearly labelled so you can see which seam is which and how they go together. 


Close up of model wearing jacket with oversized prairie collar made using Sonny jacket sewing patternHand holding denim jacket with oversized prairie collar on a hanger, made using the Sonny jacket pattern


Sonny works best with medium- to heavy-weight fabrics that hold their shape. Think denim, twill, corduroy, jacquard or wool.

If you're making the prairie collar version with collar frill, make sure the fabric is light enough to gather - ideally you will be gathering up two layers of frill fabric at once, but if the fabric is struggling you could sew gather stitches on each layer separately. Another option is to use a different fabric for the collar frill, allowing you to experiment with different textures and patterns. 

If you're lining your jacket using the Sonny add-on pattern, use slippery lining fabrics such as cupro (Bemberg), viscose (rayon), acetate or polyester lining. Alternatively, you can line the sleeves in lining  fabric and use a cotton lawn, viscose or teddy/sherpa fleece for the bodice lining.

We know some makers are planning to make Sonny as a blouse instead of a jacket - we are excited to see it! If you want to try this, use something like a cotton lawn or even a more drapey viscose, lengthen the pattern, and add an elastic channel to the ends of the sleeves.

Hand holding lined jacket up, made using Sonny jacket and lining add-on patternsFlat lay of lined denim jacket with oversized prairie collar on pink background


We have labelled Sonny as suitable for "confident beginners". While making a jacket may seem daunting, it's actually just a series of relatively simple steps. The trickiest bit is sewing buttonholes, but we have lots of tips for that! You will be supported all the way with our clear instructions, and if there are any techniques you aren't sure about, you'll find lots of extra help on a dedicated space on the blog.

If you're yet to line any outerwear on your sewing journey, the Sonny lining add-on is the perfect place to start. We did a lot of research and development to hone our instructions and you'll be amazed at the final result! 

Plus size model wearing corduroy jacket made using the Sonny sewing patternModel flicking her hair wearing denim jacket made using Sonny jacket sewing pattern

We are looking forward to seeing your Sonny jackets - both in-progress shots and finished makes. Don't forget to tag us on Instagram @TillyButtons using the hashtag #SewingSonny so we can swoon over what you're making. Happy sewing! 


Models: Averil de Souza & Sophie Prat
Photographer: Jane Looker
MUAH: Simone @ The Bridal Stylists
Samples: Sewn by Deborah Wilkins

Blue denim - Minerva
Corduroy - Lullabee Fabrics