This is a problem that many of us have because of our basic anatomy, or because it just happens to many of us as we age.
There are many solutions to the problem - this is the one which works for me.
It is based on a Burda WOF article published some years ago.
You will need to refer to the photos that I took while doing this alteration. You may prefer to download them to your hard drive so that you can refer to them more easily.
You can see the photos here. __________________________________________________________________________
1. Choose the pattern size by your hip measurement and make any further adjustments now. (I adjust the crotch length and sometimes the waist at this stage) Don't alter the back dart.
Draw in the seam lines if they're not already marked.
2. Check whether the grain line is drawn exactly down the center of the pattern piece.
Fold the pattern in half lengthwise, parallel to the grain line so that the inside leg and side seam lines are on top of each other at about knee level. Draw a new grain line along this crease if necessary.
3. Draw three guide lines on the pattern.
a) A horizontal line at crotch level at right angles to the grain line.
b) A vertical line through the dart to the horizontal line or if there is no dart, from a point midway between the side and CB seams.
c) A diagonal line from the CB seam to the intersection of the grain line and the horizontal line.
Reinforce the lower ends of lines b) and c) with tape.
4. Cut the pattern apart along the horizontal line a).
Cut the other lines down to but not through the lower edge.
5. At the diagonal cut c) overlap the top edge over the lower one by about 5/8" (1.5cm) at the seam line tapering to nothing at the bottom, and stick it down,
At the vertical cut b) overlap about 1/4" (0.5cm) at the top seam line again tapering to nothing.
6. Stick the upper pattern over the lower one matching exactly the side and CB seam lines.
7. Even out the crotch curve and side seam.
Re draw the legs of the dart from the top to where the seam lines now meet.
Extend the grain line of the lower piece to the top edge - the original grain line on the upper piece no longer applies.
[ If your pattern had no dart then add the 1/4" you have removed from the top edge to the side seam, tapering to nothing about 4" down]
8. This adjustment removes the equivalent of a fish eye dart from below the buttocks, shortens and narrows the dart and straightens the centre back seam, so reducing the shaping there.
It is likely that you will have to fine tune the side seams when fitting.
The suggested size of the diagonal overlap may be adjusted but even so you're unlikely to get a totally flat smooth seat. Do remember that you need to bend, stretch and most importantly, sit down! Don't be tempted to over fit.
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I'd welcome feed back on this. Let me know if you have any problems with the instructions. Does this method work for you? Or anything else........
ETA new link to Flickr photos - which now have the instructions in the comment section of each photo.
