Flip Face-Down Cards First
Level: Basic
Prioritize moves that reveal hidden information.
The most important goal in Klondike is to flip as many of the tableau's face-down cards as possible, as quickly as possible. Face-down cards are hidden information, and the more you flip, the more options you gain.
When several moves are possible, favor the one that reveals a new face-down card. A move that flips nothing can lead to a deadlock that's hard to reverse later.
In particular, attacking the face-down cards in tall stacks first helps clear that column and creates a chance to open an empty column.
Related strategies
Basic
The Value of Empty Columns
An empty column is a temporary workspace and a slot for a King.
BasicSend Aces and Twos Up Immediately
Move the low cards that form the base of the foundations right away.