For the incarnation, you choose the general theme, general lessons and topics to explore. The general themes and lessons for the first chakra are survival, health, procreation, basic physical labor and basic physical activities. The first chakra is also the entrance of basic energies of the universe and of Earth. It is the main chakra responsible for grounding you to physical reality.
The development of the second chakra involves mastering basic communication and social skills, basic trade, labor, housekeeping and money.
The themes of the third chakra are willpower, ego, domination, hierarchy, management, duty, devotion, honor, war, fight, struggle and passionate creativity.
The themes of the fourth chakra lessons are love, trust, intuition, kindness, healing, allowance, harmony, living in the flow, emotions and intuitive creativity.
The fifth chakra themes are high-level communications, languages, music, prayers, poetry, clairaudience - audio telepathy and communication with the spirit world. The activities of sixth chakra include the work of mind, creative writing, mental intuition, communicating with the spirit world via visual imagery.
The seventh chakra activities include direct or intuitive communication with God, prayer, understanding and fulfilling your mission in life, finding and walking your life's path and becoming a God's worker on Earth - a lightworker.
The role of spirit guides is to guide your life through the lessons and ensure that the lessons are presented to you in the proper level of development and that you receive help in going through the lessons.
The main power of the spirit guides is in the manipulation of seemingly random processes. What is random for you, is under complete control of your spirit guides, so they can create coincidences and make sure that proper help and lessons are presented to you in proper time.
Some humans can talk to their spirit guides and it is of great help. You can talk to the spirit guides in meditation and send your gratitude to them, for they are your close and powerful friends on your life path.
As i mentioned, as you move through your lessons, some of your spirit guides may leave and new ones may join. Keep in mind that most of the spirit guides are coming from the past. Many of them are souls of humans that don't have experience in modern life, so their opinions might differ from yours. Yet, they have access to the spirit knowledge and, spirit magic, know your life plan and can see a little bit into the future and know very much about what lessons, events and help is coming your way in near future.
The plan of lessons for your life is usually called a 'contract'. Usually, this contract is not binding and can be renegotiated. The primary principle of reincarnation is free will. Therefore, the result of your lessons is not predetermined. As you go through lessons, you might reach a higher level of spiritual development and earn the right to learn lessons of higher spiritual level. Therefore, your contract might be modified to include new levels. You may develop an unexpected passion and earn the right to pursue a new path.
It is very much like a computer game: you start from the lower levels and then expand to higher levels. You start from the first chakra-survival, go to the second chakra - basic communication, to the third chakra - will power, to the fourth chakra - love and so on.