Find or make some tileset images. You’ll be using these to build your maps. Save them somewhere in
Assets folder, preferably somewhere like
In Tiled, make a few tilesets and tilemaps using those tileset
images, and save them next to the tileset images. You can put the tilemaps in subfolders, like
Assets/Maps/World 1-1/Tilemap.tmx, etc.
In Tiled, make every interactive part of your tilemaps (Player, Signs, NPCs, Coins, etc.) into a Tiled object, and give the objects separate Types based on their, well, type.
In Unity, make a prefab for each of the Types you used in Tiled. You can add as many built-in and custom components as you want.
Every time you reimport the tilesets or tilemaps, those prefabs get instantiated for each Typed object and tile.
You can use
[TiledProperty] attributes to translate a Custom Property from Tiled into a regular
field in your custom