If you are a small business you can't always afford those expensive customer relationship management systems (CRM) the big companies use. More than ever you need to stay in close contact with your customers as you know small business thrives on its relationships. Without some type of database system you are unlikely to remember all the details that allow you to maximize your sales. I like to use Excel to create a customer spreadsheet and then ensure I am maintaining my relationships.
1. Excel: Put in demographic columns for name, phone, email, etc... Make sure you put in a column or two that discusses contacts and conversations.
2. Keep it Maintained: If you are selling services or pricy products you will want to keep this sheet up-to-date with sales, conversations, likes/dislikes, etc...
3. Follow-Up After the Sale: Follow-up with sale and ensure the customer is still happy. An unhappy customers won't come back!
4. Reach Out from Time-to-Time: If you want to establish a relationship you will need to check in on customers from time to time.