first you have to learn how to remove and install it.
most cars have a spark plug removal set included in its tools.
but i would also recommend using a torque wrench in the removal/installation process. because this is what the manual says. it even has the torque specifications.
to remove, turn counter-clockwise to install turn clockwise. do not overtighten.
i don't know what other peeps use but i've been using a small steel brush to clean my spark plugs. i just clean the electrode, check the gap, re-gap if needed and re-install it