The value of a properly fitted suit jacket can’t be overstated. Wearing one, a person looks well-dressed, professional and ready for the job. Without one (or in an ill-fitting one), a perfectly competent worker may appear disheveled, unprepared and entirely unprofessional. However, because most suit jackets are manufactured only in standard sizes (and because many people don’t fit perfectly into one of these “standard size” categories), finding a perfectly fitted suit jacket can be difficult. Hiring a tailor to fix the fit can also be problematic; tailoring fees can be quite expensive. If you’re relatively proficient in sewing, however, you may be capable of lengthening your suit jacket on your own.
Carefully take out the stitches of the hem of whatever part of the jacket you're trying to lengthen by using a seam or hem ripper to pull out the stitches. Be careful not to snag any of the fabric as you're pulling.
Complete your alteration job by ironing out all of the old creases left from the previous hem. While all the creases may not be completely removed after the initial ironing, over time they should become less noticeable.