The car is stock or already modified a bit? What year?
Even if the car is running good i almost would do all this anyways just so you have a good baseline to start with if you don't know any history of the cars maintenance.
Basic tune up is a good place to start:
- cap and rotor (motorcraft)
- plugs & wires (motorcraft or equivalent)
- fuel filter
- check drive belt and replace if necessary
- check timing and adjust accordingly
- oil change with motorcraft FL1-A filter
- clean MAF if so equipped
- replace air filter
Possibly changing other fluids:
- coolant (replace radiator cap if changing fluid)
- PS fluid
- brake fluid
- transmission fluid
- possibly rear diff fluid if there's a lot of miles on the car
and just check for condition and replace as necessary:
- general check of all suspension bushings and play
- tires
- brake (rotors and pads)
- battery voltage is good?
Get a feel for the car, drive it a bit and just see if you can feel anything that seems off. This will also point you in a good direction of what needs to be done.