Answer and Explanation:
Gain trust: Business relationship is sealed with trust. If you are able to make a business partner trust you, you are sure to keep doing business with them. Do not try to take advantage of them and be sure they ate not thinking in that direction.
Show interest in people: keeping up with people and always showing that you actually care, and want to assist in any way you can is a sure way to seal a client for life. Be family.
Work hard: you can not build business relationships if you are not a person that delivers. It doesn't matter if you are a nice person that always cares, if you cannot bring results and be trusted to deliver you cannot have any useful business relationship. This is the most important strategy.
Networking: networking is a popular form of building business relationships. Formal occasions, conferences, informal hangout spots, the gym are all places where you can meet new people and start a business relationship.
