Detailed instructions can be found here. In short, extract the zip into your Jubilee installation folder and run Patcher.bat. (Steam achievements will be disabled.)

• Right-click to teleport to mouse position
• F1 to see (vanilla debug info as well as) detailed position and speed stats
• F2 to set respawn location (may break local cycles)
• PageUp and PageDown to double/halve FPS Ctrl+PageUp to reset to default Ctrl+PageDown to lower by 1