How to determine the possition of keys without looking at hands

[thuyth_24]

Hi ! I've been studying piano for 1 year, I want to improve the technique and musicality of my playing piano piece that I enjoy and that is within my ability. I can play Moonlight sonata 1st mov, Fur elise and many easier pieces now. My trouble is always looking at hands when I playing. The more I looking hands, the less accuracy on both hands I get.
To improve my performance, I want to focus on right hand and not looking on the left.
Anyone know the best way to determine the possition of keys without looking at hands when playing piano ?

[indianajo]

One plays exercises that challenge ones position sense, without looking at the hands.  You should also re-learn the pieces in your repretoire without looking.  Slowness may be important, and never repeat a mistake without slowing down.  Accuracy is much more important than speed.  After accuracy has been achieved, speed can come naturally without much thought. 
My teacher insisted I never look at the hands.  My entire 7 year course of study I only looked during the first few weeks when I was learning a piece one hand alone.  
Exercises like Edna Mae Berman come in graded books, where the lower letter ones are easier than the later ones.  Exercises like Hanon or Czerny, you have to have a the teacher pick which comes next.  It is best to have a teacher anyway, to point out the many things you are not aware of that you are doing wrongly.  
Warning, if you are an adult student.  I lost my fine kinesthetic sense in my late fifties, and now have to look at my hands when jumping around.  Same result as the reason for senior professional golf leagues. The muscles do not perform the same every day after a certain age as they do for younger people.  Senior PGA starts at age 50.  

[thuyth_24]

Thank you Indianajo for your advices,
I start to play piano at the age of 30. Does exercises like Edna Mae Berman , Hanon or Czerny still appropriate for my age ?

[indianajo]

Absolutely exercises apply to any beginner or intermediate student.
Ignore the stick figures on the cover of EMB, the techniques taught are appropriate for any age.
The teacher has to tell you what the subject of the exercise is, EMB doesn't even have the Clfff's Notes at the bottom.  Each exercise focuses on one technique that is applicable to many pieces.
The difference between an adult and a child, the adult is less flexible and has full hand span.  Ergonomic stretching exercises out of a factory ergo textbook may be appropriate for an adult.  i do them at my age. 
My first teacher, my Mother, didn't worry about my looking at my hands.   After 16 months she found me a college trained teacher.  Perhaps if your teacher is not running through the exercises, instructing you on posture and flex, it is time to move up to someone more skilled and demanding.