How to Use OMGclick
Since you are reading this, I will assume you already have OMGclick downloaded and extracted to some folder on your computer and have been able to launch it without issues. If not, see How to Get OMGclick.

This article is a general overview of how to use OMGclick. For more information, refer to the various articles found in the rest of the User Guide. You can return here at any time directly from OMGclick by clicking on the User Guide button in the upper right.
Basic Function
By default, OMGclick will just replay battles until it can no longer continue due to a lack of resources (e.g. energy or keys) or some other condition that causes it to stop occurs (e.g. champions reach max level). In the case of content that consumes Energy, it will just wait until you have enough Energy regenerated to start another battle.
Controls

Along the bottom of the OMGclick UI, you will find a series of buttons. The only ones you will use often are the Start/Stop buttons and on occasion the Reload button. The F12 key can be used to quickly Start/Stop OMGclick, and Shift+F12 can be used to Reload it.
The Save button can be used to ensure that settings are saved, though this is usually not necessary. Settings are saved when most settings are changed, and settings are written to the config file automatically when OMGclick starts, reloads, or is closed. You can spot this happening when the button momentarily changes to red.
Next to that is the Edit Config button to quickly open the current config file in Notepad for quick edits/review. This is really only useful when you need to add/remove custom memory offsets from your config file.
Last but not least is the Status Messages Window button. This is used to show/hide the Status Messages Window. This button changes the state when the Status Messages Window is active.
Over on the right are the controls that enable/disable auto selling, auto forging, and auto food swapping.
Be sure to see how to Avoid Common Problems next.
Game Window
OMGclick currently requires that you play in windowed mode. If you are playing in Fullscreen mode, go into the game options and disable this. You can also press Alt+Enter to toggle Fullscreen mode.

If you are playing in windowed mode but the window is maximized, you will need to un-maximize your window. You can use the Alt+Enter keyboard shortcut to quickly toggle Fullscreen mode on then off to reset your window. Once you click the start button (you can use the hotkey F12 to toggle start/stop), OMGclick will resize the game window as needed.