Polishing, cleaning, fine-tuning… whatever you call it, its necessary before a performance. I thought I'd share some of my favorite techniques that I've picked up over the years as a student and teacher.
The first key is making sure everyone knows the dance – break the routine into 8 counts, count by count and analyze and correct everything from the head placement, arms, feet, legs (bent or straight), and tempo. If you're low on time, start at the messiest part of the dance.
Once everyone knows the dance, repetition is key! One of my teachers will not move on until each section (usually 8 counts) has been performed correctly and cleanly three times… in a row. If they mess up on the third time, she starts over. She calls it her "Rule of Three's" and uses it for only the messiest parts of dances because it can get very frustrating, but yields results.
Read more suggestions after the break!
The Dance Buzz 
A method I use is to break down key "check points" (every 4-8 counts) and then whittle it down from there. That way the performers get comfortable with the destination between movements. I find it makes the detailing process a lot easier.