Here is the sentence:
I laid down on a crunchy bed of autumn leaves at the right corner of the fence and observed the mysterious residence for movement.
I'm not sure whether "laid" is the correct grammatical term or if it is lay, lie, lied, etc.
The verb is lay down. Cuz you are using lie in this case and the past of lie is lay as an irregular verb. But lay is a regular verb too and its past form is laid. Little tricky right?