A single card is a word; a spread is a sentence. The Three of Swords next to the Six of Swords is grief followed by the crossing — a completely different reading from the Three of Swords next to the Devil, which is grief being held onto deliberately. Neither meaning lives inside the individual card.
Three mechanics do most of the work. Suit interaction: which element is conditioning which. Numeric direction: whether the numbers rise, fall or repeat. Court presence: whether there is a person in the spread and whether that person is you.
The practical drill is two cards daily, joined by one sentence, with no question asked. Thirty days of that builds combination reading faster than any amount of reading about it.