How to spell Fish as Ghoti?

Some languages like Turkish or Hungarian are "phonetic". This simply means that you can look at a word and know how to say it. English is not phonetic.

You cannot always look at an English word and know how to say it. You cannot always hear an English word and know how to spell it.

George Bernard Shaw was a famous Irish writer. He wanted to reform English spelling so that it was more logical. He asked the following question as an example:
How do we pronounce the word "ghoti"?
His answer was "fish".
How can "ghoti" and "fish" sound the same? He explained it like this:

• the gh = f as in rouGH
• the o = i as in wOmen
• the ti = sh as in naTIon