Spend time in the plant watching before your watches come along. Learning the book side is one thing, being able to apply it is entirely different.
Case in point, the ET who was Class Honorman for my Power School Class, 9201, graduated with a 3.95. I want to say that was a record at the time, but no evidence to back that up. Anyways, he gets to prototype, does well during out-hull (what the classroom time before crew assignment was called in 1993). We go on crew and he is completely inept at everything; can't stand watch to save his life, can't take logs in a timely manner at the panel, you name it, he screws it up. Fails a watch or two. Manages to pass his final board with a 2.6.
We both end up on the ENTERPRISE. Both STAR for 2nd Class within couple of weeks of each other. I qualify ELT 2 months early, get qualified Senior-in-Rate in less than 2 years, both warfare pins and transfer back to prototype as a 2nd (took PO1 test for first time month before I flew off) at my 3 year point. First Class in 5 1/2, chief in 8 1/2. The Honorman? Never qualifies SRO, gets kicked out for being fat and has to pay back part of his SRB.
Start connecting the book stuff and the plant stuff, NOW. Like withroaj said, be prepared and impress the staff with your preparation and hard work.
Best of luck and thank for volunteering!