One important tip is get out there and put up your lights before the weather changes. It is easier and more comfortable to work outdoors while the weather is mild. Climbing ladders and working on the roof can be dangerous and challenging in bad weather. It is much easier getting everything prepped in advance then just keep them off until it is time!
If you are having trouble testing all your lines you can by an inexpensive light tester on Amazon. If you pull all your lights out in advance you will have plenty of time to test and fix them with out any stress.
Your should also plan out where all the lights are going before you start putting them up this way you do not run out. Last but not least whats most important is to make the job fun. Have some eggnog and play some music.