Please feel free to discuss this project here: http://www.craftster.org/forum/index.php?topic=129855.0
Now the trend these days are the skinny jeans. Now, the fit on these depends alot on how you want them to fit, but we will get to that later.
There's probably a quicker and better way, but I find this works just as well.
1. First off, take an old pair of flared jeans....ugh much? Next, turn them inside out.
This might sound weird, but it is VERY effective. Put them on!
Mark with a pen (or something) at where you want to start to thin out the legs.Make sure you are thinning out the legs where there is NO topstitching, or else your pants will NOT turn out!
(This will work best if you have jeans that actually FIT you in the first place
Now, take some pins and pin the flare away from the inside of the leg (or wherever there isn't any top stitching.) so that if you fold it back, it looks like the skinny leg you want.
Next, carefully take off your jeans and lay them on a flat surface.
Take a ruler or a plastic quilting grid and mark a line down from the spot where you first marked, and down the trail of pins.
It should look like it is a diagonal line, going skinnier near the foot.
Reposition the pins so that they are nearer to the line you drew.
4.DO NOT CUT ANYTHING!
If you need to pick out any stitches, you will be screwed.
Now starting from the original seam, sew down the side of the leg easing into your diagonal line.
Before you do your next leg, try them on to see how they fit.
The seam should look like this:
5. If they fit properly, cut off the excess flare and do the next leg.
6. Now at this point most of you will be like, "Kay, wtf, they have this stupid lump at the knee, like this:
Luckily you have a lovely girl who has experienced the same thing, and is here to help you out.
7. You have two options: Try on your jeans regularly and pin the lumpy side, or try them on inside-out and pin the lumpy side. The last way is the craziest yet easiest.
8. Next off, mark (I just used a pin) where you want to take in the lump. Don't be afraid to sew multiple seams in one area! It's all trial and error, and the ones you don't want will come out in the end.
9. Look! YOU FIXED THE LEG!
If you didn't, just repeat steps 7 and 8. Don't worry! You will get it! I myself had a little trouble!
10. Now that you have fixed it, cut off the flare around 5/8" from the seam(s).
11. Just look at the difference!
All you have to do is repeat for the other legs and voila!
You get the point. Sweet jeans.