Holding up while cause you to jump nonstop.

Holding down will allow you to interact with things. Even if your not near something hold down and walk to it.

Jump into the well jump as early as possible, but not too early. You'll save a few frames. You want to barely make it over the well as to go down as soon as possible.

alextheman2017 discovered the floor clip and switch clip. (1 second time save) Doing the floor clip is pretty simple, just walk out the door and hold up left. (2 second time save) Doing the switch clip you must be at a very precise location on the screen and press down. I've only been able to do this once myself. It's very difficult.