Basic Pattern Drafting

Does the thought of making your own patterns leave you in a cold sweat? Does the thought of making patterns for other people make your hands clammy? Are you working from a pattern that you've gotten to fit by changing it over a number of failed tries and mistakes in good fabric?
This demonstration will show how to draft what is known as a "Basic Body Block" for the torso. After the basic block is developed, I'll go on to show how to make the pattern 'more period'. Once you get this method, you'll never have to rely on outdated or incorrect patterns again! This particular method combines both historical and modern methods to achieve a good starting pattern on paper. Once you've got that, you can move on to develop a mock-up in cheap fabric which you will then use to address any issues in fit. Once the mock-up is done, you will be able to take that apart and use it to make a paper pattern that will fit perfectly...
What and Where to Measure -
Get a fairly wide and long piece of paper. Butcher's paper or similar stuff works best and is probably the most inexpensive. You can use the pattern paper that they sell at fabric stores but it's a bit on the expensive side. The plus to is that it has a grid already printed on it. We will be developing the front and back body block simultaneously in this demo but you can do each one separately. For examples on where to measure before starting, click here. WARNING: take the following measurements while wearing everything that you will be wearing under the finished garment - that is very important.
To Start -

On your body, find your natural waist and measure from there to where the clavicle bones meet at the hollow of your throat. Draw those on your paper like the example below:

Measure around your waist and divide this by four. Take that measurement and draw a line from the bottom of your first measurement out by however much it is, like the example below:

Now measure from your natural waist to your arm pit or where ever you are most comfortable with your armseye landing. Again, refer to the example below:

Measure your chest, making sure that the tape is around the widest part of your chest. Divide this measurement by four and draw a line from the bottom of your first measurement out by however much it is, like the example below:

As you can see in the example above, the addition of green line shows where your center side is. Now measure the rise from where your shoulder measurement crossed up to where your neck and shoulder meet, like the example below:

Measure from the shoulder bone to where your neck and shoulder join and draw this line as in the example above. More green lines can now be added; the curve of the armseye and the curve of the neck opening.
As you can see, just from these seven measurements, we've now got a basic body block. This particular method is a very simplified version of the body block technique used in most costume shops. However, what this gets you is enough of a pattern to add seam allowances to and cut out in muslin in order to develop your 'toile'. The toile is the period word for a mock-up or 'muslin'. Basically, you cut it out, sew it together, and discover any fit problems from there. You can then make any necessary adjustments on the toile, take it apart, and use it to make another, permanent paper pattern that will fit perfectly and can be used over and over again.
The above block doesn't look all that period, does it? There are only a couple of little adjustments and two more measurements that need to be taken in order to make it just a bit more period.
First, add the front point. This is pretty simple and can be done without any specific measurements. In general, don't make it too wide or too narrow where it joins the waist. The other measurement, the adjusted side seam, needs two more points to plot.

Take a look at your (or your subject's) body. At the base of the spine, right along the natural waist, there are two masses of muscle on either side of the spine. Measure from the highest point of one to the highest point of the other and divide this in half. Measure out this amount from the center back measurement. That will give you the base of the adjusted side seam. Next, take a look at your (or your subject's) arm where it joins into the back, just before it curved under into the arm pit. Measure from the top of the shoulder joint to this point. Plot that point on the armseye. This gives you the top of your adjusted side seam. Now, take a deep breath and draw a gently curved line, as in the illustration above, from the base to the top of the adjusted side seam points.

Cut this newly plotted part off of the back piece and tape it to the front piece, as in the example below:

All of the above assumes that you're making a pattern for a doublet. In order to adjust your body block to make a bodice pattern, you'll need to plot your neck opening as in the example below:

Measure from the top of your front length measurement to where you want your bodice neckline to start. Measure across from this point to where you want your strap to start. Measure from there to the top of your shoulder measurement. Do the same for the back. Once you're done, measure out for the adjusted side seam like you did for the doublet. The finished pattern, with the adjusted side seam in place, should look like the example below:

You are now ready to cut out and make your toiles in preparation for fitting. Don't forget your seam allowances!
Last Warnings -
Date and label ALL your patterns. It's also a good idea to re-draft patterns every year or so. Store all pattern pieces together in an oversized envelope which is also labeled as to what it is, when it was made, etc.