The method that is important to use while writing an instruction manual is option d) "putting your instructions in sequential order."
The objective of an instruction manual is provide step by step instructions on how to use a DVR in this case. If the instructions are not provided in a sequential order, then the user will not be able to use the DVR properly.
It is not recommended to use technical language as the final user will not understand the instructions provided.
A description of the product is not useful either since it does not tell the user how the DVR works.
And finally, humor should not be included in an instruction manual.