For DF 0.28.181.40d or older: open the file in an image editor and save it as a 24-bit bitmap (BMP) if it isn't already in that format.
If necessary, convert the tileset to the correct image format for the version of DF you are using:.
( Right-Click on the tileset image and Save-As.) Each tileset is just an image, so there is no separate download link.
Download the tileset to your computer.
To use a specific tileset with Dwarf Fortress, you must perform the following steps: The exact origin of the DF font is unknown. The default tilesets (640×300 and 800×600) render 8×12 and 10×12 characters respectively, with majuscule latin letters occupying a 7×9 box, and appear broadly similar to the IBM MDA font based on the shape of the "0", "g", and "f" characters (but with slight differences including the "0", "W", and "y").