One reason this book is difficult to understand is that characters are introduced in the opening chapter in a clump without any real identity to them at first. As a result, to keep it straight, you have to keep going back to reread whose name is associated with what until you get it sorted out. Another reason is that the pace is uneven and the writing is cliche as well as minimalistic (as few words as possible). The pace is very fast, so fast it leaves us in the dust trying to sort out who did what and said what to whom (requiring rereading). Then the pace suddenly grinds to a halt, as in the cliched bathroom mirror self-description section in which Travis gives an inventory of his features for our benefit. Knowing this will arm you against the weaknesses of this "realistic" drama book as you try to make your way through it.
The summary of the first pages is that Travis has been released from juvenile hall and is being sent to a relative's place somewhere where it may be possible for Travis to get a tan in order to give him a new chance on life. His friends are cool Kirk and scatter-brained Joe. Stan is his hostile stepfather and his mother is meek and worried and someone who gets left behind, literally and metaphorically. Travis explains that his ambition is to be a writer, an ambition which annoys Stan to an surprising violent degree.