The main concept of Klappa is to have one or more action bars with hided buttons which will pop up. If you start Klappa the first time, you will see just one button in the center of the screen. This is your first bar and button togehter.

Every bar of Klappa consists of one or more main buttons which are always visible. You can extend every main button with as many popup buttons as you want. To open the option menu just write "/klappa" (/kl) or use the Klappa menu inside the Blizzard interface menu.

In the main options you can hide the default wow mainbar, add or delete a bar and open a frame with all button ids and how they are assigned.

In Wow you have 120 button ids. Nearly every action bar addon uses these ids internally, but you dont see them. If two buttons have the same id, they will to the same action if you click them. With Klappa you are free to assign to your buttons every id you want.