It's dead easy.
1 - Remove front wheel
2 - Follow the Shock Absorber (strut) up to it's top where it meets with the inner wing.
3 - Coming back down from the strut is an alloy wishbone. It's in two parts. The top part (upper wishbone mount) is bolted to the inner wing at the same place as where the strut meets the inner wing. In theory it cant move - but if it has any movement then the nuts are accessed from inside the engine compartment. There are 4 nuts - the two outer ones secure the upper wish bone - the two inner ones secure the strut.
4 - Attached to the upper wishbone mount via a long bolt that runs horizontally (it's approx 6 inch long) is the upper wishbone swing arm. The swing arm and the mount are held together with this 6 inch bolt and this is where the 2 rubber bushes which tend to fail are located. The swing arm is the alloy triangular part that has a ball joint at one end.
5 - Grab the upper wishbone swing arm and give it a decent shove (make sure the cars on axle stands - not just on the jack!!).
6 - If there's any play then you need two spanners (17mm) one for either end of the 6 inch bolt. Put one on each end of the 6 inch bolt and tighten. Dont over tighten as the bolts as you dont want to strip the threads. That said using muscle power is unlikely to strip them - it's when the garages use pnumatic guns that usually does that!
I dont know the history of your car, but from experience to date I have replaced the drop links, the track rod ends (common cause of squeaks), the upper wishbones (another common cause of squeaks and knocks) and the lower wishbones (***** of a job).
All parts are readily available (eb spares or shop4parts).
That said - if your not confident/useful with a set of spanners then find yourself a decent indy!