When something is set up in an orderly fashion, it is obvious to us that someone arranged it so. If one finds a piece of paper with words written on it, it is obvious that someone wrote those words, and that the ink did not spill of its own accord and form the shapes of the letters.

Our world is arranged in an orderly fashion:

When we look at this world, we find it to be assembled and constructed. Not one of its parts lacks connection or arrangement. For we perceive it both through our senses and intellectually, as a completed house in which every necessity has been coordinated. The sky is like the ceiling; the land is spread out like a bed; the stars are arranged as lamps; and all the objects are gathered in it like hidden treasures, each one for its particular need. The human being is like the master of the house, who makes use of everything in it. The different types of plants are there for his use, and the different types of animals for his enjoyment.

Anything arranged in an orderly fashion could not have been created unassisted:

How could one say about the world that it came into being without the intention and wisdom of One who has power? We know that anything that occurs unintentionally contains no sign of wisdom or competence. If one suddenly spills ink on a blank page, it is impossible that orderly writing and legible lines, as though written with a pen, would result. If an individual brought before us orderly writing that could not have been formed without the help of a pen, and says that the ink spilled on the paper and the writing formed of its own accord, we would hurry to charge him with speaking falsely, as this could not have been produced without intention. Since it is impossible, according to our understanding, that this could occur with regard to written symbols, how can we say, with regard to something whose workmanship is more delicate and whose artistry is infinitely more remote [from our comprehension] and infinitely deep in our perception, that it could occur unintentionally and without the wisdom and power of One who is wise and powerful? (Rabbeinu Baĥya ibn Pekuda, Ĥovot HaLevavot 1:6)

Faith means constant training. It is not acquired through a single experience of insight, but through repeatedly looking at the world and reflecting on its spiritual significance.

The most important thing is habit: Fixing in his heart and mind that everything he sees, the sky and the earth and its contents, is an outer garment of the King, the Holy One, blessed be He. In this way, one will always recall the spiritual essence and vitality of everything. This is referred to in the word for faith [emuna], which is a term of habitual activity, like a craftsman [uman] who trains [me’amen] his hands. (Rabbi Shneur Zalman of Liadi, Tanya, Likutei Amarim 42)

By considering the human self we can gain an understanding of the extent of God’s power, just as a person who looks at a map understands what the terrain looks like.

The wise person said: Whoever knows his own self knows his God. The verse “for He made man in the image of God” (Genesis 9:6), teaches that one who looks at this image understands the divine, i.e., one who looks at himself will gain from its image [i.e., from his perception of himself] an understanding of God. Although “to what likeness would you compare Him” (Isaiah 40:18), nevertheless, from the unlimited powers of his soul, which are more exalted than the physical processes, one may understand something of the exalted nature of God’s power. This is the meaning of the verse “And from my flesh I will view God” (Job 19:26): That from one’s own image, which is the image of God, one may perceive divinity. It is like one who looks at a map and understands the terrain. Even though there is no real resemblance whatsoever [between the actual terrain and the map], he will understand what he needs to understand. (Rabbi Simha Zissel Ziv, Ĥokhma UMusar, p. 197)

Further reading: For more on learning to know the Creator by contemplating the self, see p. 221.