The rules for moving cards onto Columns in the Tableau are:
If a Column is empty, any movable card may be moved onto it.
Otherwise, look at the last card in the Column: only a movable card one rank lower and of the opposite color may be moved onto it.
In the layout pictured above, the 6 of Spades (in the first Freecell) may be moved onto the 7 of Hearts (in Column 1), and the 7 of Clubs (in the second Freecell) may be moved onto the 8 of Hearts (in Column 7).
In this way, you form sequences of alternating colors in descending order. In the layout, Column 1 ends with a sequence 9-8-7 of alternating colors.
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