How you behave when negotiating can make a big difference. Here’s what to do when, according to Laurie Puhn, author of Instant Persuasion (www.barnesandnoble.com, Penguin Group, $15).

Be friendly initially to get on the person’s good side.

Be firm when you have plenty of evidence supporting your case.

Be pushy if you’re in a situation where haggling is expected or customary, like at a car dealership or a craft bazaar in Morocco.

Be calm. Always keep your emotions in check during a negotiation. However, you might want to act angry or say that you’re angry so that the person you’re dealing with realizes you might walk out without making the purchase.

Be persistent. Walk away only when you’ve reached an impasse and you know you can get the item for less somewhere else or are prepared to live without it. Otherwise, you’ll have to do the walk of shame back to the store to accept the seller’s last offer.