I have been working out in the gym, with weights, to increase the strength in my muscles.
Training in the gym/home gym is very important and should be clubbed with cardiovascular exercises.
I have done some research and on the basis of this research is how I came up with this workout for myself.
Of course there are various other thoughts of school as to how one should go about training.
I thought I will share my workout with you guys. I would love to hear from you all as to what you think.

Day 1 (3 sets of each)
Warm up exercises (should not be skipped)
Cycling or running or rowing (5-10 mins)
Squats
Leg press
Calf Raises
Lateral Pull-down
Lateral Pull-up
Bench Press
Bent over Row
Seated Row
Shoulder Press
Internal Shoulder Rotation
External Shoulder Rotation
Back Extension
Crunches
Stretches (very important again, and should not be skipped)

Day 2 (3 sets of each)
Warm up exercises
Cardio-vascular like running or cycling or rowing or cross trainer (for 30 mins)
Squats
Deadlift
Bench Press
Reverse Wrist curl
Leg Press
Stiff legged Deadlift
Side Bends in hanging position
Side leg raises in hanging position
Stretches

Day 3 (3 sets of each)
Warm up exercises
Cardio-vascular exercises like running or cross trainer or rowing or cycling (for 30 mins)
Front Squat
Sumo Deadlift
Incline Bench Press
Seated Row
Seated Leg Curl
Sit-ups with feet on a bench
Hanging leg raises
Stretches

Day 4 (3 sets of each)
Warm up exercises
Cardio-vascular exercises for 40 minutes
Crunches
Side Bridges
Twist crunch
Back Extension
Hanging leg raises
Stiff leg deadlift
Planks
Push ups
Reverse Crunches
Machine Oblique Crunches (or free style as in without machine)
Lateral Flex on Overhead cable
Stretches

Day 5 (3 sets of each)
Warm up exercises
Cardio-vascular exercises
Side Bends
Hanging leg raises
Sit-ups with feet on a bench
Push-ups
Chin-ups with overhand grip
Reverse chin-ups
Triceps dip
Squat against a wall
Floor hip extension
Leg abduction
Biceps curl
Hammer curl
Lateral arm raise
Upright row
Stretches

Day 6
Warm up exercises
Run for about an hour with varying pace
Stretches

Day 7
Climb/trek hills/mountains with a small pack and gradually increase weight and then climb/trek

If you want to work out your lower on one day and upper body on another day then do the following

Lower body exercises
Lying leg curl
Dumbbell Lunge
One legged standing calf raise using dumbbell
Seated Leg curl
Barbell lunge
One legged seated calf raise using weight plate
One legged deadlift
Reverse step up
Squats
Leg Press
Static Lunges
Kettle ball swings
Hamstring curl
Hip abduction
Calf raises
Front Squat
Overhead squat
Push press
Deadlift
Sumo deadlift

Upper body exercises
Machine tricep extension
Front arm raise
Lateral dumbbell raise
One arm dumbbell row
Bench Press
Lateral pull down
Hammer curl
Reverse wrist curl
Incline Bench Press
Seated Row
Concentration curl
Wrist curl
Dumbbell tricep extension
Bent over lateral raise
Upright row
Bent over row
Pull up
Rear Delt row
Bench Press
Push ups
Fly
Dips
Shoulder press
Internal shoulder rotation
External shoulder rotation
Curl and press
Wrist curl
Reverse curl
Finger hangs