How can you use pictures as backgrounds/tilesets?

Um, I wanted to make a background out of a picture and i have absolutely no idea how to do it.
Can anyone help???? 

First make sure the picture you want to use is a PNG image with resolution 600x240 (use your favorite image editor to modify and convert the picture as needed). Then you should create a folder named 'Gradients' in your level folder, put in the PNG image, and rename it GradientX.png (where x is a number between 0 and 255). The picture will replace Background X in the Knytt Stories editor.

to expand on the topic, create a tileset using the tileset0 template in the #KSDIR#\data\tilesets directory then save it in #KSDIR#\worlds\#LVLNAME#\Tilesets directory. Similarly to gradients, name it TilesetX.png (where X is a number 0-255) and it will replace the default tileset for that number in the editor