For by him all things were created: things in heaven and on earth, visible and invisible, whether thrones or powers or rulers or authorities; all things were created by him and for him. Colossians 1:16

God created everything the same way. . .speaking and saying it was so.

Heaven, currently, is defined as a spiritual place of relationship. It's a place where you are in the presence of the Lord.

Heaven, later, will be the restored earth with some heavenly additions, like the City of God where he will dwell. It is described in physical terms, made of colorful stones, beautiful unlike anything we've ever seen.

It will be created just like everything else God has ever made.  He'll say "Heaven" and it will be there.