I do my own oil changes and i don't own a ramp, but I bought the duralast jack system at Autozone. With it, I can jack both sides up so i can get underneath and unbolt the oil drain plug. If you can get underneath without jacks then that should be fine. I wouldn't recommend jacking one side since you want all the old oil to drain out, and I am afraid with a skewed car you may not get all of it out (unless you completely remove the oil drain pan, which I don't recommend).
And yes, I use the notches shown in the manual.