so I upload the optiloader sketch to my Arduino uno with the uno selected in the board menu?
Yes. Exactly like you would upload any other sketch...blink, your own, etc.
Also do I upload the optiloader after I connect the extra atmega chip?
It doesn't really matter. If you run the sketch without a target chip, OptiLoader will just complain it couldn't write the bootloader to the (nonexistent) chip.
Also I just went to the link and is it the optiloader.pde or optiloader.h that I need?
You need them both. Put them both in the same directory / folder on your computer.
That's the one, although I think OptiLoader will burn the bootloader to both types of chips.