This super sexy PVC underbust corset will cinch you in all the right places. 
The design is streamline, so great for under clothes, and even better worn to be seen over clothes. 

To put on, open the laces out fully, as open as can go (see pic with measuring tape at top) It is much easier to put the corset on with the laces open, and will make the corset last longer too, as trying to put it on with the laces fastened will warp the boning over time. This corset has a zipper front for easy on and off. 
To take off, also undo the back first, and losen, then zip. This again will prolong the longevity of your corset. 

For correct size, measure waist, and choose the size which corresponds closest to that measurement.
Eg. If my waist is 83cm, I would choose the L, which would cinch me down to 70cm, or if I wanted extra reduction, and want to hunt around for longer laces I would get the size down (M which has a max size of 82cm- this may be just too small, but if needed I can replace the laces to longer ones and then I could also wear the size M, and get a possible further reduction.)

S = corset open max size 78 cm, which would cinch down to 62 cm min size
M = corset open max size 82 cm, which would cinch down to 66 cm min size
L = corset open max size 88 cm, which would cinch down to cm 70 cm min size
XL = corset open max size 94 cm, which would cinch down to 74 cm min size
XXL = corset open max size 98 cm, which would cinch down to 80 cm min size