You need to do some research, you do not yet have enough information and knowledge to safely and confidently start your first cycle.
There are lots of threads on how to dose testosterone including dozens of sample cycles here on this board. Or you can purchase the e-book "Chemical Muscle Enhancement" and it will show you how to construct a cycle and do PCT, as well as supporting this board.
From what I have seen, most folks here do test in the range of 500-700mg a week (500 for first timer will work wonders) and it is often stacked with a second complementary steroid such as dbol, deca, equipoise, and on and on.
Just be sure to start with a solid plan for your cycle, and obtain all your items including the PCT before your start. Your test 250 is a start and is one of the items you would use, but you need a complete plan first.