http://s7d2.scene7.com/is/content/Newellsync/279735
Call toll free 800 number for assistance shown in online manual. (I am not posting the phone number here because of spammers posting fraudulent phone numbers on FIXYA, but manual appears legitimate.)
Unsure of your model of paint sprayer, however, mine used a 2/3 turpentine to 1/3 paint to spray without clogging. Some people unscrew the paint holder and replace it with a paint can which can hold more of the paint mixture. Hope this helps.