To make an effort with someone means to put energy (usually emotional) into a relationship. The relationship is usually a family relation, a romantic relation, or a friendship. "I make an effort to keep a strong relationship with my parents." "My boyfriend bought me flowers as a gift, he really makes an effort." "My friend always forgets my birthday, she should make more of an effort." It's a phrase that is only usually used in casual speech. But sometimes you might hear it in a work environment : "Susan is always late for her deadlines. She should really make more of an effort, or she could get fired" Does that make sense? :)