If you intend a special arm exercise, then it is better before starting to do first squat. The reason is simple enough, that is to trigger your growth hormone out. You may also need to check out the supplement at http://musclesupplementtrials.com/testx-core-need-know-order-inside-info/ to improve your training result.
Experts recommend 3-5 sets of squat exercises is enough to trigger the release of growth hormone. In addition, by doing squats before arm exercises can increase your energy during arm exercises, stimulate the nerves, and enlarge the arm muscles.
Insert a pull-up exercise in each of your practice sessions
In addition to exercising the back muscles and widening the shoulders, pull-ups also include exercises that can raise arms. This is evidenced by people who often do pull up exercises almost all have large arms.
When doing pull up exercises you should change the variables such as by adding the load and reduce repetition or reproduce repetition without additional load.
A few articles discussing how to raise arms this time. Maybe useful for all of us.