Sunroof- Squeaking- Lubricant OR?

[viper69]

I've noticed as I retract the sunroof it tends to squeek sorta as it slides across the frame of the car when it's retracted.

My GUESS is it needs to be lubricated. My questions are the following:

1. I should probably clean the parts first along the sunroof's tracks, IF so, what's the best way to clean it?
2. Assuming it needs lubricant, what should I use, and how show it applied, and how much?

Thanks