The handshake is much more than two hands coming together to serve as an introduction. The handshake is the first impression you will have of a person. It is the first time you will be touching them. This single act will not, unfortunately, persuade the opposing party. However, a poor handshake can dissuade them entirely.
You need to be firm in your handshake. It needs to be exerted with subtle control. You must gauge the other parties force and match it. If you over-exert pressure, you will stir negative subconscious feelings. Correspondingly, if you under-exert pressure, you will stir negative feelings as well. It needs perfect execution.
When you shake their hand, extend your second and middle fingers. If you can, lightly touch their wrists, where their pulse is. This will give a surge of connection in their deeper subconscious.
Another cool tip is to lightly brush the bottom of their elbow with your other hand. This gives a second, deeper connection to them.
They will carry a stronger, better impression of you if you can master this. Practice it with your friends, family, and strangers. Then go out and make a million dollars.