these are step by step pictures of installing lowering springs or even doing coilovers on a honda fit for our example we are using H&R springs.
details such as tools needed and the size of the nuts and bolts will come shortly.
starting with the rear
and the rear is done
now the front
use a jack to hold the suspension in place
remove the clips that holds the brake line to the shock body
remove the linkage with a 12mm socket
move the linkage out of the way
using a 19mm socket and 19mm wrench to remove the two bolts on the bottom of the shock body
remove the nut on the top of the shock in the engine bay with a 17mm wrench and a allen key
once you pull out shock use zip ties or anything to keep the suspension in place.
this is very important, if you let the arm fall the driveshaft can come out and if that happens it will be a pain to put it back in. trust us 
once the shock is out remove the rubber top of the shock
to remove the coil you should use spring compressors but we have a different way of doing it with two tires.
we highly recommend using a spring compressor. we do not recommend doing it our way. we did the two tire way because our compressor was broken. if you do the tire way wrong you can cause high injury to yourself or anyone around you.
once the spring is secured WITH SPRING COMPRESSORS remove the top nut with a 19mm socket. if you dont have a air gun use a 19mm socket and a allen key.
once the nut is removed, take the shock cover off
remove the whole top assembly
remove the spring from the top mount by twisting the spring
put on the new spring onto the top mount
make sure the spring is sitting correctly into the top and bottom
put the spring and top mount back onto the shock and place the cover back onto the clips
you shouldnt need a spring compressor to put the nut back onto the top of the shock and use the 19mm and the allen key
once the nut is tight place the rubber mount back onto the shock
place the stock back in postition of the car and place the two long bolts back in
place the rubber mount on the car and fasten the nut with a 17mm wrench and allen key
now fasten the two long 19mm bolts
move the jack up or down to align the linkage back onto the shock
place the linkage back into the whole on the shock and tighten with a 12mm socket
put the brake line clips back in and you're done
