1. Keep up with the work.
Learning Latin is like learning math: what we do today builds on what we did yesterday; fall behind, and it quickly becomes very difficult to catch up. Our pace, on average, will be a little more than one chapter of Wheelock's text every two classes. That means that you should work on Latin every day — don't save it all for the night before class.
2. Practice, practice, practice
You're trying to attain in one year a level of proficiency in Latin that Roman children took years to acquire (indeed, most adult Romans never acquired the level of literacy that you're aiming for). The way to do this is by constant review of vocabulary, syntax, and morphology. Do whatever works for you — flash cards, drilling with a friend, on-line drills, workbook exercises — but just do it.
3. Read, don't memorize.
That is, rather than memorizing an English translation of every sentence or passage, focus on putting all of the pieces together in Latin. The result will be a closer focus on the Latin — which is, after all, the primary objective of the course.
4. Latin isn't just different words.
Steve Martin on going to France: "I'll tell you something about the French. They have a different word for everything!"
Like Mr. Martin, many native English-speakers tend to expect that learning a different language primarily means learning different words. In Latin, though, just learning the vocabulary won't get you very far; without the rules of morphology and syntax that tell you how the words fit together, Latin sentences will remain mystifying gibberish. Commit to learning Latin grammar from the start, and you'll save yourself a lot of heartache later.
5. Compare, but don't confuse.
Latin grammar and vocabulary has a lot of parallels in other languages, and if you can use those parallels to help you, go for it. But beware! Latin isn't exactly like any other language, so be careful to approach each new topic with an open mind.