Originally Posted by outofwhack
Next question ... how to polish the bubble and keep it clean?
I suspect that this has been asked before! I've always found 210 to be the best cleaner for perspex: always wash dust and dirt off first with plenty of water and a quality cleaner, and dry with a good, clean chamois. Apply 210 with a soft, clean rag in straight, sweeping lines.
Never 
clean in a circular motion, nor rub hard in one spot to remove a mark: you'll leave a scar in the perspex if you do. Straight lines will give the least chance of sunlight reflecting on the minute score marks that sometimes get left: if the score marks are circular, there will always be a relection
Buff the screen with another clean, soft cloth after you've cleaned with 210. Don't forget to clean inside the screen, too: it's remarkable how dirty it can get.
Also, wash with clean water and a clean cloth/chamois after each flight, it's easier to get the bugs off when they're new and soft! It's worked for me for many a year now
