1. Follow directions. If the directions say the note needs to be printed on a sheet of parchment made from the wool of a lamb that is exactly 435 days old, do not use wool from a lamb that is 434 or 436 days old. But seriously, this thing is all about following directions. Margins, font, number of copies, method and time of delivery, what sources you use, etc. are all worth a sizable chunk of the grading.
2. Start early. You need to do that so you can...
3. Edit more than you write. Along with following directions, having perfect spelling, great grammer, and correct citations are key. As a 2L you're going to spend more time with the Bluebook and Chicago Manual of Style (at least I did) than you would ever want to. That's the skill they're looking for.
4. Organize everything. A dull but well-organized note will beat a genius but completely disorganized note every time.
Bottom line: this is about form over function. Get the form right, and if the function (the substance) is passable, you should be in good shape.