"Invisible" in reference to Creation would mean creation ex nihilo:
For the invisible things of him from the creation of the world are clearly seen, being understood by the things that are made, [even] his eternal power and Godhead; so that they are without excuse: - Romans 1:20
Who is the image of the invisible God, the firstborn of every creature: For by him were all things created, that are in heaven, and that are in earth, visible and invisible, whether [they be] thrones, or dominions, or principalities, or powers: all things were created by him, and for him: And he is before all things, and by him all things consist. And he is the head of the body, the church: who is the beginning, the firstborn from the dead; that in all [things] he might have the preeminence. For it pleased [the Father] that in him should all fulness dwell; And, having made peace through the blood of his cross, by him to reconcile all things unto himself; by him, [I say], whether [they be] things in earth, or things in heaven. Colossians 1:15-20
Finally, I offer the wisdom of the Jewish Mystics who use the term Ayn Sof when meditating on God The Creator. The word literally means no thing namely, that any word a man uses to describe God reduces his understanding of God to the word he used.
God's Name is I AM.
We must avoid eisegesis in our approach to scripture study. It is hard because we are believers and we want to believe. Whenever we go beyond the word of the Bible we run a risk of missing the message, yet we are children of reason, made in the image and likeness of God.
"Invisible" in reference to Creation would mean creation ex nihilo
This statement of yours, dear Sister, is presumption and supposition. You are taking the Book of Hebrews out of context and choosing the wrong words. Furthermore, God is not invisible, but simply unseen by certain people.
We've discussed this before IIRC and it would be worth starting back at Genesis 1:1 to understand it correctly. Creation ex nihilo is not a necessary condition of this creation.