very simply, by selling some shares.
for example, you buy 1000 Google shares at 100$ per share; after ten years, they are at 200 $ each, and you sell 100 shares to liquidate 20000 $.
In the bigger picture, there is little difference between (good) Value and Growth investments - only the timing and control of the payouts, and the tax consequences.
If you're 25 years from retirement, you don't want income from your investments**, you want the value of your investments to grow. When you're getting ready to retire, you'll want to convert some or all of those growth investments into investments that do generate income, because you won't have income from your job any more.
** It's OK if they do pay ...