There are many workout programs available, but most aren’t developed specifically for a soccer program.
Any good soccer strength and agility training workout should concentrate on the lower back and legs. Some upper body training does not hurt, but this should not be your sole concentration.
These should be utilized before a practice for the best results. Generally at the end of a practice players will be too fatigued to push themselves in the weight room.
Squats and deadlifts are great for working these areas, but start off light! Some soccer players have never lifts weights like this, so you don’t want them to strain or pull a muscle before a big game. Because soccer is an endurance sport, you should concentrate on longer reps as opposed to more weight.
No strength training program is perfect, but in order to know what parts to train, it’s impossible to know how to! Now go hit the gym and look forward to more powerful shots and less lost balls.