Hi Carol, It really depends on which way you turned your mower. Are you cleaning or preparing your mower for storage? Either way, you really do not want your mower tipped more than 90 degrees, or for any length of time, as this can create issues with the engine starting. Before tipping, you should also remove the spark plug and seal your gas with a a piece of plastic under the cap or drain it for storing. Another option is to put the mower on blocks when working on it. Here is an article that may provide additional helps: http://hometipster.com/how-to-maintain-a-lawnmower/
Read the article, still doesn't say which way the mower is supposed to be. Is the gas orifice up on top or near the ground when cleaning?
Lay the mower on the side opposite of the discharge if its on the side. Otherwise you tip it away from the side where the oil fill is located. Otherwise the oil will run out of the fill opening. It does not matter about gas tank fill. The cap will prevent fuel from leaking out. Be sure to pull the spark plug wire if you want to move the blade around to get all the clippings out. This will assure that the mower will not start.
oil near ground