I usually keep a few blocks around and shims. If I work on that side, I put a block under right side of frame, so that bike is at about a 10 to 20 degree angle.. make sure you turn forks to the right so it wont move suddenly. wiggle to make sure it stays. Even if I have a c-stand I prefer doing this.
Then let it set while you gather the tools.. most but not all oil will drain back. It is much easier to remove the screws and work on the gasket, or shifter or sprocket if its leaned over a bit, I find.