Draw the Waistband, Belt Loops, and Flys to Fashion Pants
Draw a traditional waistband.
Start the waistband by drawing two curved horizontal lines parallel to each other. The belt loop lines go on top of the waistband, so draw these curved lines in pencil first. When you’re finished with the drawing, you can go over it with a pen and erase the pencil lines.
Connect the lines with short perpendicular lines on both sides. Draw the center front line, a straight line directly down the center that extends below the band. The inseams will extend from the center front line when you draw the pant legs.
At the end of the center front line, draw a little z shape to designate the crotch. Add a button to the right of the center front line and draw a short horizontal line coming off the button for the buttonhole.
The placement of the button on either the right or left side of the center front line has no real rule. For men’s clothing, you usually place all buttons — regardless of whether they’re on shirts, jackets, or pants — on the right side (so the buttons are on their right when they’re wearing the garment unbuttoned).
For women’s clothing, buttons are typically placed on the left side. However, it’s become a trend in the apparel industry to put all buttons on pants, especially jeans, on the right side.
At this point you can leave the waistband simple with only the button, or you can add belt loops.