As is often the case in essays that do not argue one side or another of a controversy, but rather state a point of view, the first task of the essayist is to state a illustratable point of view in the thesis statement, toward building a body of evidence and examples to illustrate and support his/her point of view. So ask yourself, “What are the most important traits in a true friendship?" You might want to preface your actual thesis statement with some observations about the process for cementing a friendship – how one does not "look for" a true friend exactly -- one does not consciously , intellectually decide to seek a friendship, but rather a true friendship grows from acquaintance to shared experiences, to loyalty at crises, etc. As you enumerate the actual qualities of a true friend, your thesis statement will become clear to the reader.  Example:  "Paramount to cementing a friend of a lifetime is the automatic unspoken forgiveness for each other's imperfections."