Hi,
similar to HP's first method but remove the spark plugs so it will spin quicker and under less stress until you get oil.
Pouring oil back down the feed pipe to Oil filter can work or if you have some clear( you want to see it coming) 1/2" hose stick it down the feed pipe hole in the block and suck the oil up through the pump. I tend to do this if you don't get oil fairly quickly using method one.
Terry