This thread is an awesome tutelage guide for what not to do when seeking fit and style for leisure wear, while almost ignoring the same for proper business, informal, and formal attire. But, what is one to do when seeking the best fit and style for their chose leisure wear fashions?
Please watch the following video for how to measure your success with fit and style.
If you cannot perform as these gentlemen demonstrate, including sitting down, without unbuttoning or unfastening your coat, jacket, or waistcoat, then you have failed to achieve proper fit for your leisure wear. This is doubly true [ha!] for those that prefer to wear the double breasted jacket which was meant to substitute for the wearing of a waistcoat/vest under a single breasted jacket such that your companions and contemporaries would be spared the indignity of gazing upon one's belt buckle or exposed and unsightly waist.
Although the fashion of their leisure costumes changes from that of a youthful peacock to a more sedate and refined middle of the road fashion, before reaching the fashion apogee of leisure wear: the stroller, their respective fit and styles do not change. Each costume is styled in a manner peculiar to each performer as regards their lapel width, gorge,button stance, etc, in a manner that camouflages their respective differences and defects, while keeping a uniform fashion appearance.