Since I only have a push mower I dont need to change directions as much, so I usually just mow the longest way for a few times and then I switch it to the other directions. Sometimes in peoples front yards who have a tree, I mow doing circles around the tree. It looks nice!!
IF you mow the lawns every week you can USUALLY see the previous weeks pattern OR you just
remember what you did the week before.
BUT you gotta remember --
your memory is the third thing to go !!
Just switch lines and absolutely no circles . I dont think they EVER look nice keep your lines straight and change directions every week unless you want to eventually have permanent lines/ruts.