Count five seconds down and five seconds up. This slow burn gets deep into the core of your muscles and builds them from the ground up. Eliminate momentum, ensure continual load.
Try between four and seven multijoint exercises per 60-minute workout. Multijoint exercises aren't nearly as scary as they sound. It's just any workout that uses two muscle groups. For example, an assisted chin-up uses biceps and latissimus dorsi (your big back muscle)—two joints at play.
Some other workouts you can try include leg presses, dead lifts, overhead shoulder press, bent rows, dips, incline machine bench press, etc. Learn more about multijoint (compound) exercises here.
Exercise your entire body in each workout: This produces most metabolic output and hormonal output. So you might do 10 to 15 of each of these exercises: leg press, bench press, dips, and bent-over rows.