Christ invites us into relationship with God though him. As Christians, who are called to imitate Christ, we are to extend this invitation to others. Among most Christian denominations, that which we share in common is far greater than the differences and the points on which we disagree. To a large extent, the differences have led to the many denominations that we have today. These denominations serve as communities in which we can practice our particular beliefs among others who share those beliefs.
Introducing one's denomination to a conversation is a secondary consideration. It is appropriate in response to the direct question, if asked, or in response to questions such as, "Why do you believe that?" Focusing on denominational differences could be a stumbling block in a nascent relationship with a person from another denomination or someone new to the ideas of Christianity. Too great a focus on denominational differences could lead to an "I'm right, you're wrong" outlook, which is not helpful. However denominational affiliation may emerge in the conversation or relationship, the focus should be on unity, not disagreement.
A statement that has been variously attributed (and mis-attributed) but nonetheless holds true with many as a Christian view is, "In essentials unity, in non-essentials liberty, and in all things charity." (The sentiment matters more than the attribution.) The essentials to many are faith, hope, and love. These should be universal among Christians. In non-essentials, there is freedom. Christians are united in the essentials without requiring uniformity in all things. Of course, there can be disagreement over what is essential and what is non-essential, but we should live in charity (love) with one another as we seek to advance the Kingdom of God. We can agree to disagree and continue to live in peace with one another.