Photo studies

All pics are from Hot Topic, modified by me. Click on image to see larger version without red lines.

2 pair of tight pants:
Notice how there are folds at the crotch. Especially on the denim pants you can see that the folds are more accentuated on her right leg. When the leg is lifted and pushed forwards it creates folds of surplus fabric.
Notice how the fabric is smooth on the thight and knee as these parts are pushing the fabric. And that movement creates folds on the side of the thigh and around the knee. On the left leg the fabric is more in a relaxed state.
In the back view you can see how the fabric that is pushed against the front of the right thigh creates folds moving from the crotch to the knee. Behind the knee the fabric sort of bundles up and the lower part of the leg only has a relaxed fold going downwards.
On the backside of the left leg you see a bunch of small folds across the thigh as the fabric is pushed backwards by the leg. These are less accentuated on the denim pants as the fabric is stiffer and they also have a closer fit.
Also notice how the upward movement of the left hip creates small wrinkles on the left buttock in the dirction of the movement.
You will see that the lower legs are pretty relaxed in back view as they hang loose pulled by gravity, while in the font view the fabric bundles up as it rests on the shoes.
The loose pants are different; they have more relaxed folds. There are folds where fabric is pushed together (crotch) and where it bundles up (at feet) but the fold on the legs hang more losely because the fabric is not pushed the same way by the body.

Now to the tops...
1: Notice how the fabric is smooth around her breasts. The tummy part is not as streched out and has small folds where the top 'climbes' up a bit. Notice how the folds are not completely straight but follows the curves of the body.
2: Much looser fit. You get folds where the sleeves are pushed inwards by her arms. The shirt is smooth but not streched over her breast and folds under her breasts as it is hanging loose here - it's resting on her hips and bottom, thus the across folds of a little surplus fabric.
You see folds where the shirt is pushed by her shoulders.
3: Folds under her arms where the sleeves are pushed in. The upper body is turned slighly up and to the right - thus you get no folds in the right side and the fold to the left and middle is being pulled up up, her right breast being the highest point.
The left shoulder is pulled back from the body and creates a few folds from the shoulder towards the chest.
And notice how her sleeves are pushed up creating a lot of surplus fabric, especially where the arm is bent. These folds cling to the arm and show the shape of the arm because the sleeve is tight.
4: Very loose fit. His arm is slightly bent, but as the sleeves are so loose the folds don't cling to the arms. They hang loosely and make folds where the fabric rests on the arm. Lots of bundle up action where the hands in the pockets pushes the shirt together and also where the bottom of the sleeves rest on his hands. You can see that the shirt hangs from his chest; the fabic is smooth over the chest and makes a few relaxed folds under it.

The last thing I wanted to show you was some skirts:
1: The fabric is tight (I mean reeeal tight LOL) on her bottom and makes folds across her tummy and her hips because of the streching and 'climbing' down of the skirt. The skirt itself has lots of folds as the skirt is pulled by gravity... this thin soft fabric makes lots of folds. Notice how her right leg is pushed forward and changes the direction of the folds.
2: This is stiffer fabric... it fluffs out more and creates big wavy folds, a lot fewer that the first skirt.
3: Again a good example of how the movement of the body shapes the folds. The right knee is the point that pushes against the fabric and draws folds from it (or to it, whatever)

Alright, enough photos for now.

>>> next page, A few examples of drawing folds >>>