I am a fitness enthusiast who wants to build some muscle. Some info about me: I am 22 years old, 69 kg, 179 cm tall. I have been working out for about 3 years now, and I have some strength, but I fail to add size. Going to the gym and lifting weights is not available to me for now, and probably won’t be for a while, so working out at home is the only option I have. What I’d like to know is what kind of workout routine should I do to build muscle without equipment (the only equipment I have is a pull up bar). I have some well toned arms, shoulders, abs, quads, hamstrings and a relatively strong core. Although I can do a lot of push ups (and different variations of it) with added weight (a backpack I fill with books) my chest are pretty small, and so are my back and calves. My goal is not to be too big, I’d be happy if I add 3-4 kg of lean muscle (in the right places of course). An example of how I’d like to look like:

Can you tell me of a complete workout routine to reach my goals (what exercises, how many reps, sets, rest between, how many times a week, what muscle groups should I work on what day, etc etc…)? I suppose that I’d have to increase my calorie intake for this, so help with the diet would be great too. Thanks!

Anyone who can answer me?

Building mass is high weight, medium reps (6-10) at rep max.
This can be done using body weight exercises, ideally by adding weight using rucksack, weight bearing belt etc. It is however very hard work, because you will have to be very aware not to let technique slip while adding enough weight to make these rep ranges difficult.
Balance will be very key too, and is the area many body weight only training systems totally miss. Push ups have tricep as prime mover, as do dips and many others, any pull ups will have biceps as prime mover so arms get severely overworked, and don’t get chance to recover and grow.
The balance system I was taught is BALS (back arms legs stomach) in truth this is pull push legs core as below.
Wide grip pull ups
Push ups
Squats
Plank
Simple balanced set of compound exercises. The difficulty would come in on squats, due to weight needed, less books more lead, sand bags, or iron in a strong bag, or on a scrap scaffold pole which can be picked up for very little or sometimes nothing.
Check out the body weight training section for more variety.