How to measure
Measure from the tip of the shoulder down to the bottom of the sleeve
Place the measuring tape at the corner of one shoulder and pull across to the other shoulder. This is an important measurement as some people typically wear the same size but have different shoulder widths.
Measure from the bottom of one armhole across the chest to the bottom of the opposite armhole.
Place the measuring tape in the middle of the collar and pull it down vertically to the bottom of the jacket.
For measuring the waist first button the jeans up. Next spread the jeans flat on the surface, and remove any fullness and wrinkles from it.
With the jeans buttoned up, spread the jeans on the floor or table; next remove all wrinkles, and measure this region by starting from crotch seam spot to the spot of the waistband.
Starting at the crotch seam and ending 1–2 inches below the hip area.
With the jeans buttoned up, spread the jeans on a table, floor or any other flat surface, with outseams on both corners. After removing all wrinkles and any fullness, measure the length from the top of the waistband.
Having the jeans buttoned up, spread the jeans on a surface flat. Now measure the inseam gap from the crotch, at the spot where the front and back seams meet, exactly where, depends on the length you desire ultimately.
Now in the last step follow the same pattern as the previous steps, that is spread the jeans on a flat surface e.g. table or floor. After removing any fullness or wrinkles, start measurement beginning from one side of the leg opening to the other side of leg opening.