The Major Arcana Tarot Card allocated to the sign of Aquarius is the Star card. The general meaning of this card is hope, unexpected help, the future and clear vision. Aquarius is also the sign of friends and associations, as it rules the 11th House.
The Minor Arcana Cards of the Five, Six and Seven of Swords have less obvious connections to the sign of Aquarius. To begin with, each Suit corresponds to an element, and the Suit of Swords corresponds to the element of Air, the intellectual or mental plane. Since Aquarius is an Air sign, it corresponds to the Suit of Swords.
When a Decan Wheel is consulted (see image below), the first Decan of Aquarius is found to correspond to the Five of Swords, Lord of Defeat (January 20 to January 29.) The second Decan corresponds to the Six of Swords, Lord of Earned Success (January 30 to February 8). And the third Decan corresponds to the Seven of Swords, Lord of Unstable Effort (February 9 to 18). If your Sun sign is Aquarius, you can determine which minor card is “your” card by seeing where your birthday falls within the Decans, by consulting the chart below. It can be used as an alternate Identifier, or you may contemplate how the card is thematic in your life. Additionally, using the Decan Wheel allows for time to be introduced into readings.
What exactly is a Decan Wheel? A “Decan Wheel” divides a circle, which has 360 degrees, into 36 10-degree segments (“dec” means 10.) Each of these 36 segments correspond to one of the Minor Arcana cards in the Tarot, excluding the Aces and the Court Cards. The 36 segments are grouped into 12 groups of 3. The 12 groups are the Zodiac signs, and the 3 within those groups are the Cardinal (1st decan), Fixed (second decan) and Mutable (third decan) sub-aspects of each sign. So for example if your birthday is October 6, your birthday falls within the approximate 10- day segment of the 2nd decan of Libra. This indicates your birthday is a Fixed sub-aspect (the 2nd decan) of a Cardinal sign (Libra), and corresponds to the 3 of Swords. Reflecting on your particular set of aspect & correspondence will undoubtedly inspire insights about yourself and your life.
Sources:
Tarot Correspondences by T. Susan Chang
Tarot Deciphered by T. Susan Chang & MM Maleen
Qabalistic Tarot by Robert Wang