My base.
Start with a waistband. I'm a bit of a hipsters fiend, you can put it however high or low you want.
It's your call what you want your jeans to look like. I've got three styles here, but I'm only going to use the middle one for the full tutorial. The shading style can pretty much be used for any style of jeans, you'll just need to edit it for the width of the jeans leg.
Right, I'm using the middle outline. I've put some curves in the outline at the knees and around the feet. If the jeans are cut-offs then they're not going to crease as much at the knees because they'll be able to fall and straighten out more. Using the 1 and 2 put on the details at the top (belt loops can look a bit fussy on small bases, your call) and around the ankle, using 2 for the seams. At the moment I'm using black instead of 1 because I just like outlining in black first, I'll change the colour once I start filling them in.
Take 3 and start shading. I'd colour over most of the black lines that were inside the leg as those were more for shading guides, I find they look too dark if left in the outline colour. These shading lines can be as long and thick as you want them, if they look too big and dark (or indeed too thin) then you can change them later, I usually tweak the shading as I go along. Make the creases at the top of the leg sharper by making the lines in 3 longer, thinner and closer together. I've also added a couple of creases at the bottom of the pockets but these aren't really necessary and would probably look silly on very baggy jeans unless there was actually something in the pocket.
Now fill it in the rest with 5.
Build up the shading with 4. Like I said, now's the time to colour over any bits of 3 that look to dark when zoomed out (you'll want to zoom out a bit as you go along so you can see how it's turning out). Don't worry too much about outlining every single bit of 3 with 4, especially where the sharper creases are.
Now use 6 to add highlights. If you're using a bigger base you might want more colours (likewise you'll want fewer on a very small base), but I think this is enough for a base this size. Don't forget to add shading and highlights to the details at the top, these aren't just for the creases.
Use 7 and 8 to add the little poppers on the pockets (not all jeans have these, I just think they look nicer), and a button.
