You can build muscle relatively quickly, however, one week or less is unfortunately an unrealistic goal. If you really want to build the muscle then this will take a considerable time.
You need to set your self some realistic goals, so firstly lets change the time period to 2 months. Secondly i am going to assume that you have access to some kind of gym, or at least some dumbells/barbells.
There is no point in trying to just increase chest size; you would most certainly look weird and out of proportion. For this reason we are also going to look at increasing upper body strength and definition.
So now i have a few concepts for you to understand.
1) To build the most muscle you use low repetitions and high mass
2) You will make far better gains when you record the mass you lift and the repetitions completed
3) You must always push your self for one more repetition
4) Rest and Relaxation is a necessity
For each exercise you do you must find a weight that you can lift, but that puts you out of your comfort zone and makes you work; for example for a bicep curl, find the weight of a dumbell that you can perform 5 repetitions with (the fifth repetition should be a struggle). This is the mass that you will use for the exercise in your first training session.
To build upper body strength you can use the following exercises:
There are obviously other exercises as well, however this will give you a good workout and good results.
Planning your workouts is crucial for you to make the most gains. So workout the mass you will be using for each exercise (not press ups) and write the mass down in a table.
The table should look something like this:
___________|___Workout 1_____|___Workout 2_____|
Exercise | Mass | Repetitions | Mass | Repetitions |
Bench press | X | Y |
Bicep Curl | X | Y |
Preacher curl | X | Y |
Dumbell flies | X | Y |
Press ups | - | Y |
Where X is the mass used, and Y is the repetitions completed - repetitions is filled in after the exercise is completed in the work out.
At the beginning of every workout you must aim to beat the repetitions in your previous workout, so check what you did before and beat it!
Once your repetitions get to 8 (or 10 - it's up to you) its time to increase the weight on the dumbell/barbell - back to a weight with which you can only do 5 repetitions.
You must not over exercise as heavy weight lifting and training is very hard on your body. Make sure to only work out 2 (3 times maximum) a week. The workouts may only last 15 to 20 minutes at a time, but they will be very high intensity, so don't think you are getting off lightly.
If weights are not available to you then you can use bottles of water (1 litre = 1 kg) and put them in a bag or rucksack, this can be just as effective! You may also find other ways to improvise, it depends on what you have available to you. You can also leave out preacher curls, or improvise for that as well. If you don't know what the exercises are then you can google them, or watch demonstrations on youtube.