Practice Closer to the Basket
The most important thing in shooting practice (outside of proper mechanics) is repetition. The more reps you can get in your workout, the more valuable and effective your workout will be. You will always miss shots so there is always a need to get the rebound. By practicing closer to the basket, you will use less time chasing the ball down thereby leaving you more time to shoot.
Have A Plan
If you really want to be a good shooter, don't go out to "shoot around." Have a plan, what do I want to improve on, what drills am I going to use, how long do I want to spend on each thing before I go to the next shot? Organization will help you get the most work in the in best amount of time.
Practice time is always limited, either by facility or personal schedule. It is easy to say, "I am going out to practice my shooting for an hour." As we discussed above, in your hour practice, you spend a certain amount of time chasing and rebounding, not shooting. So in your hour, you don't really get in an hour of shooting. Instead, set goals. Try to get in 400 shots in your workout. If you run out of time before you meet your goal, work harder the next day (it will help your conditioning). If you have an open-ended period of time, go for 400 makes instead of shots. Pick a number that will challenge you but is attainable. Keep track of makes and misses to help you track your improvement.
Isolate Your Skill
When trying to improve your shooting, it is important to isolate that skill to maximize the use of your time. Shooting practice is not time to work on ballhandling passing or any other skill. Work on only the things that directly relate to your shooting. Want to be a 1-dribble shooter? Fine, work on that. But, this is not the time to work on combination, 4 dribble, double spin, crossover jumpshots. There are other times and places for that. If you want your shooting practice to be effective, you have to spend your time shooting.
Use Same Shot Repetition
Not all shooting practice should be game-like. Shooting is all technique, rhythm and consistency. Those are things that need to be addressed in your shooting workout. Consistency is build through muscle memory that is build with repetition. There is great value in taking 50 shots in a row from the corner, then 50 from the wing, then 50 from the top, etc. Get yourself in a rhythm, get every shot to be the same then move to the next spot. Put this into your practice plan (see above section). After you are comfortable that your shot is grooved, then move on to your "game-like" shooting drills.
All your shots should feel the same. That is your goal. When they all feel the same and you don't have to think about your shot, your repetitions will produce the results you are looking for.