As others have mentioned, the "normal" way to learn to play blindfold is to simply get better at chess. A strong amateur will be able to play a game blind without much specific training. This is due to chunking—being familiar with lots of patterns makes memorizing those patterns much easier.
That being said, there are specific exercises which can help a weaker player play blindfolded:
Become extremely well versed in coordinates. It is impossible to play Blind without this. See this trainer for instance.
Tactics involving deep calculation. Deep calculation while looking at a board is essentially the same muscle as holding a position in your head.
Quiz yourself on the color of each square. This will help you get a feel for the board.
Mentally move single pieces around in your head. Especially knights and bishops (long diagonals can be tricky). Write down 10 of these moves and check that they were legal afterwards. You should be able to do this reasonably quickly.
Practice. Lichess has a Blindfold setting where the pieces vanish. Not quite as good as proper blindfold (you can still see the board...) but it's a good stepping stone.