how long does it take to get muscular
It'll take anywhere from 1-2 years to put on your first 20-25 LBS of muscle. So assuming you follow the instructions/examples, you'll get a noticeable amount of muscle in your arms within 3-6 months. Don't be discouraged, it's not a very long period of time and it'll fly by before you know it.
There are factors that will dictate how long it takes to build a muscular chest, including how frequently you train, the volume of your workouts and some genetic factors. It can take up to eight weeks of weight-training to see significant improvements in muscle size.