I'm guessing this is the first time you have serviced a car

. Here is your checklist in priority order.
Oil - Get the correct grade - see instruction book and note that sports (thin) oil can actually cause damage in an old or low performance engine. use a funnel if you have shaky hands - you don't want oil on the engine.
Oil Filter - I prefer to avoid non brand makes as the filtration is sometimes much worse.
Sump washer - Never use the old sump plug washer - keep a few as spares.
Plugs - Get a good quality brand with a copper core electrode (quads, splits and triples not really necessary for most road cars.
Filter - air filter - really easy replacement drops in.
Checks
Anti freeze - gravity guage will do this for you and top up.
Washers - top up washers with a screen cleaner (Not washing up liquid!)
Oil - Fill to top of mark on dipstick NEVER over or UNDER the lower mark
Tyres - check pressure, if low suspect a slow puncture and check thoroughly
Brakes - check there is some pad left and brake fluid level. (Do not leave the top off as it sucks in water vapour and this is really bad for braking.)
Tools
You'll need a oil filter removal tool (if sandpaper doesn't work)
Spark plug tool (tighten by hand then quarter of a turn under the wrench).
Spanner for the sump plug
Screw driver for the air filter housing (many have snap on clips instead!)
Ok guys so what have I missed?