What is the best way to: How to best mow the lawn

OPT:
[a]. Using a lawn mower that's running, walk back and forth pushing it over the grass to be cut. If you go diagonally it gives it a cool look.;
[b]. Borrow a goat from a nearby farm if you don't own one and let that goat hang out in the yard as long as possible so it can eat the grass and keep it cut.;
Answer:
[a].