Every time I work on shooting with my basketball players they always start off with three to four form shooting drills.  These basketball training drills are meant to develop consistency and repetition through balance, alignment, and follow through.  A basketball skills training drill that focusses specifically on upper body form, and promotes arch and follow through is the One Knee Form Shooting Drill.  

The One Knee Form Shooting Drill is an excellent warmup for shooting.  However, it is imperative that the player maintains proper form during this drill.  One common mistake that many players will make  is they will have a tendency to cock their arm back in order to get the ball to the rim.  This happens because because players cannot use their legs during this drill.  Be sure to correct the players on this mistake and make sure that they are using arch and follow through to get the ball to the rim and not unnecessary upper body movements.  

The video below shows the One Knee Form Shooting drill being performed.  Other variations of this drill include shooting from both knees or shooting from a chair, and any one of these is a must when starting out your daily shooting sessions.