1) Use a helper! It is tough to get accurate measurements if you are also trying to keep your corgi standing and not wiggling or running off.
2) Width is very important, since it is not adjustable on about half the carts. Do not pad the width. You can make a simple measuring device by taking a piece of cardboard and cutting it into a U shape so the inside width is about two inches shorter than you think your corgi’s width is. Try to slip it over his hips, then widen it until you can. Measure the new width, and record it in the comments section of the application.
3) Widen the cardboard further until it just slips over the shoulders at their widest spot, and measure it. This is width at the shoulders.
4) Length and height are adjustable, so try to be accurate, but you do not need special devices to measure these.
5) Hip width is fixed in many carts. If you are not sure about the width, include circumference of the widest part of the hip in the comments section.
6) A picture helps us to know if your measurements seem accurate or not, so please include one if you can.