Anybody hoping to become or remain a keyboard player or performer needs technical practice to maintain any level of skill. The Hanon finger exercises for piano offer a simple first-choice solution.
Extra care has been taken to provide a beginner-friendly introduction to these standbys. Click through here (same window).
Check out also the Schmitt Op. 16 exercises for piano - out of copyright so facsimile copies are available free all over the internet. This collection of exercises also has a creeping-up-and-down selection (Nos. 172 to 213).
Brahms's 51 Exercises for piano are for more advanced players, and you should approach them with care. 'Pushing through the pain' can permanently damage your hands!