Today I had a discussion with Marie about backing fabrics, to check what I need. I tried out backing on plain cotton, cotton drill, and with just interfacing. I decided on plain cotton as it gives it some structure but isn't too bulky so will still give it that crisp tailored look. For the sleeves, I won't need any backing, but will reinforce the cuffs and tops of the sleeves with interfacing for support. 

I then bought the 1 metre of plain cotton needed from the store, so I can get the cutting out and flat tacking to top fabric done over Easter.