[header] How to install pergo flooring [title] Prepare the floor. [step] Clean any debris off the floor and secure any loose floorboards before attempting to install anything over the sub-floor. Make sure the sub floor is level with a carpenter's level. 
Floor leveling is usually only done on concrete floors, but you can find speckling product at the store that you can apply with large putty knives, if you've got a few spaces out of alignment. You can also just install pergo over the floor, even if it's a bit uneven, but you risk cracking or separating the tiles eventually.