Debug 64

Debug 64 is a hack which uses the HackerSM64 and SM64 Debug Features.

In-order to enter the debug level select, hold L while the game is starting up. To select levels, use the D-Pad. To enter the level, press Start
In-order to enter the flying/free-move mode, press D-Pad Up while you are in a stage. To move Mario, use the analog stick. To move him up or down, use the D-Pad. To make Mario only rotate, hold Z while moving. To exit the flying/free-move mode, press A
In-order to toggle the debugger (or whatever you want to call it), press D-Pad Up while holding L.
In-order to switch modes in the debugger, press L and use the D-Pad to select the mode. Then press L again to switch to the mode.