A lot has been written about proportions for sewists.

Jackie is semi-fitted. This means there is room to wear layers underneath so the key fitting area is at the shoulders and neckline. 
Threads has a good article about adjusting patterns for your size. It’s a tried and tested article.

Petite
BurdaStyle has a good post about petite adjustments
Craftsy writer Julia posted some details about petite pattern sizing
Bunny at LaSewist petites her patterns from the word go.

Personally I’ll check a few points on the pattern and see if they match with my proportions
– shoulder to bust; shoulder to waist, 
– neck to shoulder
– shoulder to hips
– pocket placement.

One thing to keep in mind, these are not rules. If you love jackets with amazing features, factor these features in. I did a Google search on ‘oversize badly made jackets’ and frankly they all looked great to me.

Jackie can be your statement jacket of the season if you use oversized collars and pockets.

Talls
BurdaStyle has a post about shortening and lengthening patterns.
Adjusting patterns for tall people isn’t my area of expertise but there are lots of sewing bloggers who are.


Lena has already covered the basics for adding and removing length to your pattern.

Proportions
Pattern changes to balance this jacket for your shape is what I focus on. 

Bust darts
All I’m going to say here is wear the right support. Check where your bust sits and then adjust the dart for your reality. I reduced the dart by 2.5cm.

Pockets
A standard pocket can be too deep for small hands. A standard pocket might not be big enough for your needs ie, wallet, phone, organiser, wads of cash.

And standard pocket placement can be lower or higher than your arm’s reach.

On skirts and pants, I shorten my pockets. Basic pocket patterns tend to end at mid-thigh on me, when they should end at the top of your thigh. So I tend to cut them back so they can at least fit a credit card in my pocket ie. no longer than 6cm or 2 1/2″ if the pocket starts at my waist.

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The pocket bag is a bit deep for me so I’ve skimmed 2.5cm off the pocket base. When I make Jackie again, I’ll place the pocket 2.5cm towards the side seams.

Collars
Again, you might have a Cleopatra neckline so your collar needs to be wider.

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I tend to slim back my collars so they don’t cut into my chin ie, lack of neck:)

I lowered the collar 1cm from the top so that it covers my neck in the cold but not feel like I’m being strangled. However I took another 0.5cm off the collar when I sewed the facing to the collar. 

Note: I dropped the buttonhole on the collar by 1cm so it would still sit centred on the slimmed collar. This is a decision you can either make or disregard.

Sleeve cuff
This is another proportion decision you might consider.

You can make your sleeve cuff wider for a feature or slim it back. The choice is yours. I kept the sleeve cuff and kept it wide. This doesn’t affect how I wear Jackie and the sleeve cuff is part of it’s style.

Too much to take in?If this is all too much information to digest, make a test version out of calico and see how the test jacket fits on you. This approach is the safest method and you can practice those bound buttonholes and welt pockets with less stress.

If you have very little spare time to test the pattern, measure the widths and length of your suggested size minus the seam allowance and check those measurements on you. This takes a whole lot less time to achieve than making a test version. This is a risky approach, so take all the measurements twice!