Allah sent down 4 great books to his Prophets for the great guidance of mankind. He has always instructed His servants how to connect with Him. 

Allah’s guidance is the greatest guidance to the smallest guidance. He sent His guidance through the Prophets. Right now there are no prophets. We only have the Quran or Sunnah. So how do we know Allah is guiding us? 

There are many signs that we can see. Allah guides us through our thoughts or through our friends. We may read a surah in the Quran and really relate to it. This is guidance from Allah!