Hanon's Foundation of Piano Technique

Learning piano is a very physical endeavour as well as an intellectual - and, some would say - spiritual one.

In order to prepare the hands appropriately for piano study, the student - young or old - would be well advised to purchase and study one of the great books of exercises of piano technique. 

I would recommend Hanon's The Virtuoso Pianist in 60 Exercises.  

Hanon not only covers the important elements of wrist and finger "mechanics" with 60 practical exercises from Volumes 1-3, it also emphasizes the need to strengthen the weaker fingers (ring and little finger) to attain evenness between all the fingers, so that, for instance the classical runs in Mozartian keyboard phrasing are played in a fluid and perfect fashion without a hint of odd notes. 

These techniques ultimately give the student the complete control required to play pianissimo or fortissimo where required, or play with accents, or marcato, staccato, legato etc.

If you are reading this article and you are just a beginner, please bear in mind, that for something like learning the piano, you have to look at the long term aims.  You cannot perfect pieces or hand technique or strengthen the hand evenly in a matter of weeks, you must dedicate months and years to the process.  Some quality time spent with Hanon will make all the scales and difficult technical exercises until Grade 8 and beyond seem relatively easy.