Firstly measure your waist measurement. My teacher at fashion antidote told me to move the tape measure around at your waist by loosely pulling back and forth until you find your true waist which is the smallest part of your body on the torso. It's easy to think its lower than it actually is. Then you need to take the hip measurement which is the fullest part around your bottom.
I would re-measure yourself even if you think you know what your measurements are because if you are anything like me I do this infrequently assuming I don’t change that much. There isn’t any point in putting the effort in and getting the fit wrong so it’s best to double check.
The next measurement you want to take is your waist line to your hip line. And finally the length you require the skirt to be from your waist to above, below or on the knee. Don’t go too long or too short. It's useful to have someone else to help with taking these measurements down as they are easy to get wrong inadvertently on your own.
My measurements are -
Waist – 78 cms
Hip – 105 cms
Waist to hip – 23 cms
Length – 60 cms
The next bit requires a little mathematics but don't let that put you off as it really is very easy. Sometimes it's about breaking each section down before moving on, don't get fazed! Get your pattern paper ready and turn it on its side and draw a straight horizontal line along the bottom of your paper to the length of your waist to skirt length – in my case it would 60 cms long. This will form the centre back line of your sloper, or the skirt length. You should mark the left hand end point as point one and the right hand end point as point 3. Now you are ready to go!
To illustrate how the skirt sloper will look when drawn on to pattern paper take a look at the image below. It has point numbers on it from 1-22. The measurements and simple sums you will be asked to do will be transferred from point to point.
Next you want to measure down the centre back line – from points 1-3 to mark off point 5 which is the waist to hip measurement. I have a measurement 23 cms so I measured down the line and squared off accurately towards point 6 on the centre front line. This will be your hip line and also the line you would put a zip in to etc…. When you sew up the canvas to test the fit this would be the part of the back seam you would leave open so you can get into it.
Now you want to create the hip line across your sloper. If you quarter your hip measurement and add 1.5 cms ease you will have the distance to the side seam on your sloper – the line that goes from point 7-8. For me it would 105/4 = 26.25 +1.5 = 27.75cms. Take your ruler and across the squared off line from point 5 draw a line away from you to that length. Square down to point 8 on the hemline.
To get your hip curve you need to measure across the top of the sloper to where the curve of your hip starts – this is point 1-9 in the diagram. To get this measurement you need to quarter your waist measurement and add 4.25cms. For me it was 78/4=19.5+4.25=23.8cms. Take your ruler and draw away from point one to this measurement. Then put your ruler on point 9 and align it with point 7 and draw a dotted line from point to point, extending the line above point 9 by 1.25cms to get point 10. You should now also draw a dotted line from point 1 – 10. The reason that these are not solid lines is because they will not be your final hip curve or waist lines – as neither the waist nor hips are straight! It will make sense later.
To get to point 15 you need to half the measurement of point 1-9 – for me this was 23.8/2 = 11.9cms. Mark off this point, square down and measure 13cms. Mark the end of this measurement as point 16. This is the base of the dart on the back of your skirt sloper. To create the dart itself go back to point 15 and measure 2cms either side of this point and mark the measurements up. You can then draw the dart lines from point 16 through the marked up points either side of point 15 until you reach point 1-10. Draw a cross on point 16 and draw a couple of lines up and away from either points at the top of the dart to create a triangular shape at the top of the dart.
From point 16 draw a line directly downwards to the hemline. At the point it reaches the hemline this becomes point 17.
The next measurements will construct the front of the skirt block and we are almost there! Promise!
To get point 2-18 you need to quarter the waist measurement and add 2.25cms 78/4=19.5+2.25=21.8cms. Draw from point 2 towards yourself to this measurement and then place your ruler on point 7 to 18 and draw a dotted line. Extend the line by 1.25cms and then mark the end of the line point 19.
To get the mid point of the dart – point 20 – you need to divide the distance between point 2 and 19 into 3. For the sake of ease I am rounding my figure up to 22cms – so my measurement would be 22/3 = 7.3cms. From point 19 draw the length of your measurement and mark this point as point 20. Square downwards from point 20 and measure 10 cms and this point is the base of your front dart. Draw a cross over this dart point and mark it as point 21.
To make the dart measure 1 cm either side of point 20 and then draw down to point 21 and draw a couple of lines up and away from either points at the top of the dart to create a triangular shape at the top of the dart.
From point 21 draw a line directly downwards to the hemline. At the point it reaches the hemline this becomes point 22.
Now extend you hip line across to point 6 and draw a line between 2 – 4 to create your centre front line.
The final thing you have to do is curve your lines. This needs to be done on the front and back of your sloper at your waistline and hip between your waist and your hip line – as I mentioned earlier these points on your body are not straight. This is where the curved element of the pattern master comes into play or your French curve. Between point 10 and 7 and 19 and 7 curve off your hip line. Then you need to curve off the waistlines between points 1-10 and 19 -2. Then you are done!
Now you have measured and drawn out your pattern make sure to label it - put what it is, front skirt, back skirt, hip lines and centre front and centre back etc...put who the measurements relate to or a size if you are doing a standard size.
Phew! Next time you will need to add seam allowances to your pattern pieces and make up a toile to fit it properly.