It's the word, (elohiym) that is plural, not God.
The word, (elohiym) is similar to the word, (sheep). The word, (sheep) has a plurality to it in that it can refer to one sheep or many sheep but it's still the same word.
The word, (elohiym) can be referring to one God or many gods but it's still the same word.
Scripture tells us clearly that God is one so the plurality of the word, (elohiym), when referring to God, is in the singular, in the same way, if I was referring to one sheep the word, (sheep) would be singular.
The word, (elohiym) is similar to the word, (sheep). The word, (sheep) has a plurality to it in that it can refer to one sheep or many sheep but it's still the same word.
The word, (elohiym) can be referring to one God or many gods but it's still the same word.
Scripture tells us clearly that God is one so the plurality of the word, (elohiym), when referring to God, is in the singular, in the same way, if I was referring to one sheep the word, (sheep) would be singular.