When you are finished shaving apply ice cold water to the area shaved. A few seconds of torture will shave you some long term discomfort and problems later. Once you are cleanly shaven and your skin is dry, apply a toner to your skin. If you skin tends to be damp and stickey, you may want to apply a light powder, but be sure to brush all the excess away. You are now ready to begin.
TAPE is likely the single most important ingredient in the whole cleavage process.
My recommendation for tape is a medical tape by 3M called Transpore. It has a ribbed finish to it and is elastic but with pretty good strength. Now attach the tape under your arms and angle it slightly downwards and just under your nipples where the tape can also be pressed in place. The rest of the tape can just hang loose until you have done exactly the same procedure on the other side. At this point you can grab each end of the loose tape as shown below.