Practices define the attitude of a team. 
Are you practicing correctly?  Most of a basketball player's practice time is solitary and most of the games are 'pick-up' games.  Do you know a player's solitary practice time can make a basketball player better or worse?  Are you creating and/or reinforcing good habits or creating and/or reinforcing bad habits?  How do you know? 
Video! Set up a video camera, record your practice drills and learn how to play better.  I suggest you record all your team training sessions and when you're practicing alone.  While reviewing your practice videos become intimate with the rewind and fast forward buttons (or you'll waste lots of precious time watching meaningless footage) and the slow-mo button so you can really study in detail. 
Why should you record your team training practices?  You're able to review your coach's nuggets of wisdom, get to know your team's propensities, your teammate's individual and team propensities and your own team and individual propensities.  If you can get someone to shoot videos of your games a review of game footage makes for wonderful team practices (an overhead view covering the entire basketball court is the best perspective for this specific purpose as you're able to see how, why, when and where systems and situations develop and play out within the ebb and flow of your games).

What are you looking to discover while reviewing your practice, practice drills, training, coaching and game videos?
Change hats, remove your basketball uniform, don a coach's whistle and stage your own basketball camp. 
As a coach how will you train that player and/or team to add, remove or improve behaviors and habits? 
Often you'll find, removing bad habits and poor behaviors produces faster results than adding or improving on good habits and good behaviors.  Allow me to repeat that last nugget;
often, you'll find removing bad habits and poor behaviors produces faster results than adding or improving on good habits and good behaviors.
Always look to simplify; "Occam's Razor;' one should not increase, beyond what is [absolutely] necessary, the number of entities [or movements] required to explain [or do] anything." 
When a player is coaching, two grandiose things happen for you, your team and your coach.  You and your team learn how to play better basketball and become empathetic with your coaches.  You also become more aware of the positions that you normally don't play.  When you're more aware of the other positions you become a better team player. 
Now, because you are videoing and studying your practices your skills, your teammates' skills and your teams' skills are growing rapidly; simultaneously you're becoming easier to coach.  One feeds upon the other in perpetual motion; a positive feedback loop. 

Is it good to practice by yourself?
There are literally thousands of solitary practice drills players can adopt.  I propose you explore many practice systems at your local library.  In one afternoon, pulling books from the basketball section, a player or coach can find solitary practice systems to rapidly improve any skill from any level to any level.  See the list of books below to help you get started. 
Most players spend most of their solitary practice time shooting.  Unfortunately most players spend most of their solitary practice time drilling in incorrect shooting behaviors and creating bad shooting habits.  There is a way around this ever growing problem, learn to shoot properly from the book, "Basketball - It's All About The Shot."  Then watch the video of your solitary shooting practices to refine your new good shooting habits.  Once you have developed your good shooting habits you can spend more time improving your other skills.  L

Look, basketball is an easy game. 
On offense a player looks to score or advance the basketball to a scoring position by passing or dribbling or placing one's self or one's teammate into an optimal position to score or to receive a pass to score. 
On defense, as individual players and as a team, stopping the offense from scoring or advancing the ball to an optimal scoring position, the exact opposite of offense, is the objective. 
So study yourself and your team using video and introspective study.  Find all the weakest areas, whether that be skill levels or basketball IQ, then find a book, a video, a camp, or a routine that increases your skill level and your basketball IQ. 

Contact me, 'Your Personal Basketball Shooting Coach,' if you're unable to locate the information you need on your own, I'll do what ever research is necessary and spoon feed you the information.  Then, as Nike says, "Just Do It!"  Learn to take responsibility for your actions and your education.  Others can guide you, but only you can be you.  Basketball players are made, basketball players are not born; great basket ball players are self made, not only by working on their skills level but by studying the game (basketball IQ), learning the game, and remembering 'Occam's Razor'. 

Only Perfect Basketball Practice - Makes Perfect 

The Following Books Are Recommended Reading For All Coaches and Players (you can find them in your library):
Beginner Players / Coaches:
Baffled Parents Guide to Great Basketball Drills by Jim Garland
Basketball Skills and Drills by Krouse, Meyer, Meyer
Teach'In Basketball by Bob Swope
Coaching Youth Basketball by American Sports Education
Drills and Skills For Youth Basketball by Grainer, Rains

All Players / Coaches:
Basketball Handbook by, Lee H. Rose
Coaching High School Basketball by Bill Kuchar
Basketball Tip-Ins by Nick Sortal
WBCA's Defensive Basketball Drills by Women's Basketball Coaching Association
WBCA's Offensive Basketball Drills by Women's Basketball Coaching Association
Attacking Zone Defenses by Kresse, Jablonski
101 Offensive Basketball Drills by Karl, Stotts, Johnson
101 Defensive Basketball Drills by Karl, Stotts, Johnson
101 Rebounding Basketball Drills by Karl, Stotts, Johnson
Coaching Fast Break Basketball by Ellis
Zone Offenses For Men's and Women's Basketball by Harkins, Krause
All Purpose Offenses For Mens and Womens Basketball by Harkins, Krause