Men's trousers have many names, but can be categorized by shape into four types: straight trousers, bell-bottom trousers, tapered trousers, and loose trousers. Trousers come in a variety of designs and functionalities, and can be worn in many ways. Even just considering side pockets and back pockets, there are many variations. The design of the front panel also varies depending on the intended use, such as the presence and number of pleats. Leg openings typically come in two types: rolled-up and straight, but there are also special leg openings like the horseshoe cuff. Because of the diverse designs of trousers, matching them with jackets is very important. Generally, they are single-pleated dress trousers. They can be worn by anyone, regardless of age or profession. Common fabrics include wool, cotton, linen, and synthetic fibers.
Front Panel. Begin drafting from the front panel. Take 1/3 of the crotch circumference as a margin for the hip measurement, and add 2-3 cm to H/4. On the crotch line, divide the hip circumference into four equal parts, and extend to the left by 1/4 of the thickness (front opening width). Draw the hemline by taking the crotch length downwards from the midpoint of the crotch seam. The knee line is 5cm above the crotch length below the knee. The hem width is 11cm on each side symmetrically opposite the crotch seam.
Generally, after moving 0.5cm-0.7cm inwards from the waistline at the front center, connect to the crotch rise curve. However, in special cases, due to the calculation of excess weight, the front crotch rise curve needs to be offset from the front center and raised further upwards. The waistline is W/4 + 3cm~4cm. Draw an arc-shaped side seam line past the hip line, extend the side seam line upwards by 0.5cm, and then redraw the waistline. For the waist pleats, take 3cm-4cm from the crotch seam towards the side seam and draw a line towards the intersection of the knee and crotch seams. For the crotch side seam, first connect the hem to the crotch seam, then move 1cm inwards from the knee line and draw an arc. Draw the crotch line with the same width as the knee line on the front side, equal to the width of the side seam.
The back piece is drafted based on the front piece. On the crotch line, advance 1cm inward from the back center; on the waistline, advance an inward "●" measurement. Connect these two points and extend upwards by 3.5cm. Add 2.5cm to the thickness of the back piece (back opening width) compared to the front piece, and draw the back crotch curve. For the waistline, take W/4 plus 2cm for dart allowance, and redraw the waistline 0.5cm upwards. Increase the width of the knee and hemlines by 1cm on each side. Draw an arc downwards from the "opening" measurement on the waistline and hipline. The inseam line drops 1cm from the crotch line, passes through the knee line, and connects to the hemline.
