A transposition cipher doesn't change any letters at all. Every letter of the answer is already in front of you; they have simply been written down in the wrong order.
Count the letters. If the frequencies look like ordinary English — plenty of E, T, A, O — but nothing reads, the message has been reordered rather than substituted.
Rail Fence The message was written in a zigzag across 3 lines, then read off line by line.
TREASURE MAP
3 rails
TSMRAUEAERP
Every letter of the answer is already in front of you — they are simply in the wrong order. Counting the letters is the first useful thing you can do. This one is Rail Fence. The key: 3 rails. The message was written in a zigzag across 3 lines, then read off line by line. Rebuild the grid, read it back in the original order, and the first letters come out T R E. The answer was TREASURE MAP.
Find the shape the writer used: how many rails, how many columns, which route. The letter count is your best lever, because it tells you which rectangles the message could have been written into.
One a day, three guesses, and a streak that breaks the moment you miss one. Today’s is cipher #1.