Its somewhat difficult to separate a ball joint without a seperator and not damaging it. If you have a big hammer you uncrew the nut for the ball joint until it is on the last few threads and hammer the control arm with big impacts. Im sure others have different methods. I'd recommend a ball joint seperator though. Or you can be really careful with a pickle fork...but at that point you might as well order a new ball joint lol.

 

Leaving the nut on, just tap the side if it with a sledge and gravity will pull it down.

 

For the ball joint removal you may want to play with the position of the ball joint. I know sometimes even with my ball joint seperator they dont want to come out unless the ball joint is totally square becuase of whatever pressure is put on it...they are a very tight fit and wont want to come out for nothing so play with the position and it might just pop right out...