my directions are digramming sentences. the sentence states:

Question

I will be happy when I graduate from high school.

Answer 1

Here is an excellent website that will show you how to diagram sentences:
http://members.cox.net/teachro/

Click on Diagramming and then on Compound/Complex sentences. You are working #7.

Let us know what you come up with, and we'll be happy to comment.

Answer 2

The independent clause is:

I | will be / happy

The dependent clause modifies "happy."