Ahhh!!!
are you gay or something! Whats with all this "slimming the pecs down" and "tonning"?
next you'll want a "flat tummy".
come on!
1st I thnk you need to read up a bit on the body and names, or we'll both just get confused.
www.exrx.net will help. have a good look around.
and there is no man-word for toning. Toning does not exist, its made up.
you gotta choose wether you want to build up your muscle or strip down your fat.
you say you want flat pecs, this is where we will get mixed up. the word "pecs" means the pectoral muscles, these are muscles. Muscles can be made bigger (good) bye training and good diet, or smaller (bad) by not doing training.
The word "chest" reffers to the whole chest area, including bone, muscle and fat.
now then do you want a smaller chest?
if so then you need to loose weight from all over your body by doing exercise and eatting healthy.
I'll be back in 12hours from now.