Staying in front of your customer past customers is so important. One way or the other you have to have regular contact with them by way of mail, email, or a phone call. Keep asking for the referrals! I have found that since I made this a everyday part of my business I have gotten so many referrals from my past customer. And good thing about it is that it will keep happening with those new customers, until the majority of your business is from referrals. It is very exciting!!