Silence is golden, often saying nothing is more powerful than anything you may want to say. Silence can be very unnerving for the other party and they may begin to speak to fill the vacuum created by silence. This may lead them to disclose more than they may have given out at the first stage during negotiation.
Keep on Listening
Make sure you are intensely listening and practice the art of summarizing and clarifying as they speak, make sure that you give them signal that you are listening intensely and encourage them to continue. Nodding your head or use of words like - I see, Hmmm can be useful in negotiations.
Ask clarifying questions - what did you mean by that?
Probes - "Why did you say this?
Motives - What led you to that position?
Don't negotiate assumptions - negotiate facts
Keep your cool
Sometime the other party may use emotional barrage to derail the negotiation process. Let the other side blow off steam and vent frustration, don't react. Return to main issue or take break in case it gets very acrimonious. Don't walk into the trap of derailment.
Whatever be the situation never assume that you have lost it completely. Stand up for your rights. These situations teach you the most in life; this is where you really have to negotiate! In negotiations caring deeply may not cut ice, only effective preparation and focused attention make the difference
Reduce your pace of speech
At time we speak at approximately 120 + words a minute and lord almighty has bestowed us with the ability to listen to 240+ words a minute. So there is no need to panic and rush, there is enough time. Use tone modulation and depth of voice to convey honesty and seriousness. In your speech build in pauses so that you can watch the impact your words are having on the other ball mill party during negotiations.
Reserve your firepower and trump card
You should not offer more concessions if you have been cornered hammer crusher, every concession you give needs to be reciprocated. Encourage the other side to spell their needs and delink it from the positions they are taking to defend it. You should also spell your needs and then barter them with each other in the end. Offering too many concessions in the starting may reduce value creation in negotiation.