A 3x3 followed five weeks later (four weeks on, one rest week) by a 5x5 program.
Squats, deads, benching, snatches and power cleans. Supplement this with rows, dips and chins, lunges, millitary presses, cuban roations and bent lateral raises. Add to this plyometrics and core/neck training and football specific agility and footwork and skills drills.
Lift three days a week and warm-up with some ladder drills and other footwork and stretch, work on agility and plyos twice a week. Sport-specific meaning, back-pedal, run routes, work on getting out of your stance, catch passes or throw 'em, hit the tackling dummy, take hand-offs or practice handing-off, work play-action et al.
And by-God, eat man ! EAT !