Getting trousers to fit is tricky, so here are some tips. Start by taking an accurate measurement of your hips at the widest part and select the pattern size based on this measurement.
Make a toile just of the top section, like a pair of shorts, but without the waistband. Use a longer length stitch in a contrasting thread; this makes it easier to remove if you need to alter. If your waist measurement is larger than the pattern size, do not stitch the back darts at this stage.
Try the toile on inside out, this makes it much easier to adjust. If the waist is too loose, remove the toile and stitch the darts. Try on again and if the waist is still too loose try pinching a little from the side seam if this gives a better shape.
Once you are happy with the toile transfer the alterations to the pattern. Or better still trace off a new pattern with your alterations, you can then refer back to the original pattern should your shape change.
When deciding on the length, measure the inside leg of trousers you already own as a guide, then add a little extra. Again try the trousers on inside out to turn up the hems and pin. Remove the trousers and tack the hems before trying on the right way out. Finally stitch the hems in place.
The beauty of perfecting a trouser pattern, is that its one of those items you’ll make time and again, once you’ve got a great fit.