First, you should now the rules (common sense)
and get familiar with them.
For non chess players, tiles as the Knight/Horse might be confusing at first.
You will get used to it. After a few puzzles you might understand.

It is important to understand a few things:
- how to move the Knight (as stated above)
- how blocking tiles work
- how to put pawns in the equation
- what is symmetry and how can I use it
- how to break a problem down

No game spoiler included. Take note how the different tiles can attack differently. The King attacks the Queen and vice versa. Can the Queen attack the Rook? The Rook attacks the Queen? Neither can the Queen attack the Rook, nor vice versa: The tiles in between block the path. Without the blocking tiles, of course the Rook could attack the Queen. It still couldn't attack the King, as it is blocked by the Queen. Can the Knight attack something? The Knight can take the King AND the Rook as well. Neither blocking tiles nor your own pieces matter.

This section contains no game spoilers. It's something to think about.
Think a moment. How many ways do you see to place down the two Rooks, if the Task would be: "Put down the Rooks in different corners. The Rooks shall not face each other, but be placed diagonally. They shall not be able to attack each other. Don't yet think in Pawns. Think only about Rooks."
Well, here you have an example of perfect symmetry. There are many ways to put down the two Rooks (12), but: There is only one way to put the two Rooks into opposing corners diagonally. Not 4, not 2, 1. There is no difference in the placement in THIS case, as it can be mirrored. This means of course, we have less branches to get through positions.


Now consider this: If you put down just 2 bishops, which shall be able to attack each other: Is this the only way to do it? It is. The middle is blocked. And no matter how you turn it around, the board remains the same. Perfect symmetry.

Now evaluate both positions again.
The two Rooks: Would it matter, if Pawns are envolved? Do we get more possibilities now?
No, as in this case, just to name one reason, the Pawns cannot attack the Rooks, Still a perfect Symmetry.

The two Bishops: Would it matter, if Pawns are envolved? Do we get more possibilities now?
YES. Rotate the board 180° Both Bishops could be attacked by Pawns, IF they were involved - of course, NO is considered correct, if you understood my question in that way as to consider this very example. No PAWNS are around.

Conclusion:
Valuate if you get perfect symmetry to consider less board positions. If Pawns are envolved, look, if the Pawns could attack. If not: Perfect Symmetry.

Try to figure out, what kind of combinations are impossible. Which Tiles never go together. A very common example is: A Tile is being attacked by 2 Rooks - from the left, as from the right. Or a Rook and a King. Etc.

A good place to start in many cases is the placement of two similar Tiles. Look how many positions there are to put them down; then you can follow down each branch.