There is a section on better understanding what makes up a hymnal, including the indexes. This is valuable in explaining how to use all the indexes in Praise For The Lord, for example. The last chapter in the first half of the book is on the subject of introducing new songs to a congregation. Gradualness don't try to sing too many new songs at one time. Repetition follow up the introduction of a new song with a second look at it, and then a third.
Perseverance make the learning of new songs a long-term program.
Sydnor includes a discussion of what makes a hymn singable. This will help song leaders predict which songs the church will learn quickly. The second half of the book is a general discussion of how to improve congregational singing. It includes chapters on the use of hymns in the worship service, in the education program, and in the home. There is also a chapter on planning special singing services.