Change your ads regularly. Your prospects could get bored seeing the same ad all the time. Statistics show people usually see the same ad 7 times before they actually buy. Just change them enough to keep them from being overexposed. For example, if your ad said. "FREE Killer Marketing Ebook!", you could change it later on to "FREE Sizzling MarketingEbook!
Lower the chances of negative wordofmouth marketing. You'll always have customers who are dissatisfied. Try to please them as much as possible. You could give them a refund, discount, a free product, a coupon, a rebate, a compliment, etc. Just be polite and stay calm if they are angry or frustrated with your business.
Give people a deadline to order. Tell people if they order by Sept.15, 2002, they will get a discount or free bonuses. This will create an urgency so they don't put off buying...