How do I convince a Traffic Commissioner Hearing that I can have an LGV licence after a DD offence?

Ihave applied for an LGV licence, but since i was convicted of DD in 2006 i have to attend a hearing. I did not attend a Rehabilitation course, and I don't have a definite offre of a job. What kind of reference do i need? And what is the best way to ensure the decision comes out in my favour?