With no motor in the car the best you can do is snug the adjusters up enough that the car it not resting on the bump stops.
If you have 2-3 husky friends about 600-800 lbs worth.... They could be an engine stand in. But even at that it would be a ROUGH adjustment.
Nut shell version.
There are a couple points on the suspension that get measured and then the adjusters are adjusted. The car gets bounced a couple times then measured again. Rinse and repete.