If your delight is in souls, love them in God, because they too are frail and stand firm only when they cling to him. If they do not, they go their own way and are lost. Love them, then, in him and draw as many with you to him as you can. Tell them, 'He is the one we should love. He made the world and he stays close to it.'
Augustine, Confessions IV.12
One of the most striking things about the life of Augustine is the number of friends he managed to make and keep throughout his life. He was a man of many friends and a man who loved his many friends well.
The quote above comes at the end of a section in which Augustine discusses the dangers and benefits of friendship-love. In keeping with ideas he developed around the same time in On Christian Teaching, he argues that love of neighbor should rightly be subordinated to, and caught up in, love of God. Love of neighbor (i.e., love of particular beings who are created in the imago Dei) can only be genuine if it is rooted in an overriding love for the Triune God as the creator, sustainer, and redeemer of those beings. Thus for Augustine friendship always included persuasion to become a member of the Church in order that the love of friends might be caught up into the divine love. This well explains how many of the friends whom Augustine led into heresy in his youth later followed him back into the arms of the Church.
This points to a two-pronged lifestyle of evangelism that we would do well to cultivate: a love for friends and neighbors that Augustine modeled in his hospitality and his copious letter-writing, and a consistent, explicit witness to the ground of that love in the Triune God. Christian, love your friends in God, and draw as many of them with you to him as you can. You don't need a slick evangelistic method or every apologetic answer. All you need is love. (The rightly-ordered kind).