We are back at the table with a design I have wanted to show you for a while. It is a crossover front top, the sort of thing that sells for several hundred pounds, and I worked out how it is made by studying one closely when I was working for a designer in Hollywood.

The construction is simpler than it looks. The front is elongated, seamed only part of the way up, and then the two panels cross over one another and fasten at the side. Everything else is a choice.

I draped it in jersey first, then again in a softer muslin, because the fabric changes how much ease you need and I wanted you to see that side by side rather than take my word for it.

Demonstration Steps:

• Sketched the theory first from a body sloper: elongate the front, sew the centre front only part way up, clean the sides, then let the two front panels cross.
• Pinned the fabric at the centre front on the form and found the point where the seam stops and the drape begins, which is what sets the whole look.
• Brought each panel across to the opposite side, pinning at the side seam, and noted that a small tuck or pleat at that point buys extra drape if you want it.
• Made the underneath panel slightly more fitted and the top panel more draped. That contrast is what stops the crossover looking bulky, and it is entirely your decision how far to push it.
• Showed the version with no centre front seam at all: cut straight, pin at the neck and shoulder, then shorten and clean the centre, which gives a straight or boat neckline instead.
• Adjusted the neckline by relaxing the fabric where more drape was wanted, then re-pinned, because on the form you can see immediately whether the fold sits well.
• Worked out the fastening options: stitch the crossover into the side seam, or leave it loose with a small button or snap underneath. Both are legitimate, and the snap keeps it adjustable.
• Marked the pattern on the fabric: neckline, shoulder, armhole, side seam, the fixed point where the panels meet, plus the centre front and the apex as reference lines, and the dropped waist.
• Decided the sleeve treatment last, dropping the shoulder slightly for a softer armhole, and made sure the split area at the underarm is cleanly finished either way.
• Re-draped the whole thing in a softer muslin to compare. In muslin you need noticeably more room through the crossover than in jersey, and seeing both makes the reason obvious.
• Noted that when opened flat, the front panels flare rather than hang straight, which is what gives the hem its slight A line.

Questions & Answers:

• Q: I have a sloped back and I am not sure how to adjust it. If I had side seams and the centre back open I could adjust it.
• A: Then do exactly that. For a woven version especially, you want a side seam so you can get in and out of it, and a centre back opening with buttons or a zip gives you somewhere to make that adjustment.
• Q: I have made the blouse in muslin to fit check it and I am adjusting the darts.
• A: Good. When you transfer to paper, mark the dart but do not close it yet. On the bias every fabric behaves differently, so fit it on your body first and you may find you need much less dart than the muslin suggested, or none.

Next week I will show how to get to this same top from your torso sloper rather than by draping, so you do not have to start on the form if you would rather not.

I also need to develop new slopers for myself, because my measurements have changed and almost nothing from last year fits. That has to happen before I make my Ascot dress.

I want this top for myself in a longer version with a proper sleeve, so we will be coming back to it.