According to the text, self-instruction is particularly useful in helping students who
a. have significant skill deficits across all academic areas.
b. have difficulty responding appropriately in situations that evoke strong emotion.
c. have demonstrated an inability to demonstrate compliance with the more procedural aspects of classroom functioning.
d. have not responded to instruction in basic self-monitoring.

Self-direction is a learning method used to help students understand as they are instructed and give themselves a direction that they ultimately obey. It is, in other of words, the mechanism of self-regulation, or self-command.

It may be useful for students who are hyperactive, and who may have direct instruction issues as well as people who elicit unique strong emotions, too

Also, students with learning disabilities will find self-instruction very useful.

An example of self-instruction is strategy is the W-S-T-C. This means

What are you going to do about the situation/problem?
Select a strategy for the task you'd like to perform
Try the strategy
Check and evaluate if the strategy works

Cheers!