Hare Krsna -Below is a short summary from Srimad Bhagavatam (3rd printing 1977) of how the creation of this material world takes place. For those who want to know how that it took more than 6 days and then the Lord rested, here is a more exacting description.
Damaghosa das
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SB 3.5.23 -The Personality of Godhead, the master of all living entities, existed prior to the creation as one without a second. It is by His will only that creation is made possible and again everything merges in Him. This Supreme Self is symptomized by different names.
PURPORT -...As explained in Bhagavad-gītā (9.7), the material creation takes place at intervals by the will of the Lord, and in the periods between dissolution and creation, the living entities and the material energy remain dormant in Him.
SB 3.5.24 -The Lord, the undisputed proprietor of everything, was the only seer. The cosmic manifestation was not present at that time, and thus He felt imperfect without His plenary and separated parts and parcels. The material energy was dormant, whereas the internal potency was manifested.
SB 3.5.25 -The Lord is the seer, and the external energy, which is seen, works as both cause and effect in the cosmic manifestation. O greatly fortunate Vidura, this external energy is known as māyā or illusion, and through her agency only is the entire material manifestation made possible.
SB 3.5.26 -The Supreme Living Being in His feature as the transcendental puruṣa incarnation, who is the Lord’s plenary expansion, impregnates the material nature of three modes, and thus by the influence of eternal time the living entities appear.
SB 3.5.27 -Thereafter, influenced by the interactions of eternal time, the supreme sum total of matter called the mahat-tattva became manifested, and in this mahat-tattva the unalloyed goodness, the Supreme Lord, sowed the seeds of universal manifestation out of His own body.
SB 3.5.28 -Thereafter the mahat-tattva differentiated itself into many different forms as the reservoir of the would-be entities. The mahat-tattva is chiefly in the mode of ignorance, and it generates the false ego. It is a plenary expansion of the Personality of Godhead, with full consciousness of creative principles and time for fructification.
PURPORT -The mahat-tattva is the via medium between pure spirit and material existence. It is the junction of matter and spirit wherefrom the false ego of the living entity is generated. All living entities are differentiated parts and parcels of the Personality of Godhead. Under the pressure of false ego, the conditioned souls, although parts and parcels of the Supreme Personality of Godhead, claim to be the enjoyers of material nature. This false ego is the binding force of material existence. The Lord again and again gives a chance to the bewildered conditioned souls to get free from this false ego, and that is why the material creation takes place at intervals. He gives the conditioned souls all facilities for rectifying the activities of the false ego, but He does not interfere with their small independence as parts and parcels of the Lord.
SB 3.5.29 -Mahat-tattva, or the great causal truth, transforms into false ego, which is manifested in three phases—cause, effect and the doer. All such activities are on the mental plane and are based on the material elements, gross senses and mental speculation. The false ego is represented in three different modes—goodness, passion and ignorance.
PURPORT -A pure living entity in his original spiritual existence is fully conscious of his constitutional position as an eternal servitor of the Lord. All souls who are situated in such pure consciousness are liberated, and therefore they eternally live in bliss and knowledge in the various Vaikuṇṭha planets in the spiritual sky. When the material creation is manifested, it is not meant for them. The eternally liberated souls are called nitya-muktas, and they have nothing to do with the material creation. The material creation is meant for rebellious souls who are not prepared to accept subordination under the Supreme Lord. This spirit of false lordship is called false ego. It is manifested in three modes of material nature, and it exists in mental speculation only. Those who are in the mode of goodness think that each and every person is God, and thus they laugh at the pure devotees, who try to engage in the transcendental loving service of the Lord. Those who are puffed up by the mode of passion try to lord it over material nature in various ways. Some of them engage in altruistic activities as if they were agents appointed to do good to others by their mental speculative plans. Such men accept the standard ways of mundane altruism, but their plans are made on the basis of false ego. This false ego extends to the limit of becoming one with the Lord. The last class of egoistic conditioned souls—those in the mode of ignorance—are misguided by identification of the gross body with the self. Thus, all their activities are centered around the body only. All these persons are given the chance to play with false egoistic ideas, but at the same time the Lord is kind enough to give them a chance to take help from scriptures like Bhagavad-gītā and Śrīmad-Bhāgavatam so that they may understand the science of Kṛṣṇa and thus make their lives successful. The entire material creation, therefore, is meant for the falsely egoistic living entities hovering on the mental plane under different illusions in the modes of material nature.