Some say each point represents a pathway, or the "seven rays of manifestation of the Higher Self."
1 - power, personal will and determination
2 - unconditional love, wisdom and growth
3 - knowledge and intelligence
4 - harmony and tranquillity
5 - the powers of mind and science
6 - devotion and honesty
7 - magick.
Another idea is that the points signify the seven magical elements - earth, air, fire, water, light, life and magic - or the inner and outer elements - earth, air, fire, water, heaven, earth and self. Whilst a further suggestion is that they represent the seven directions - north, south, east, west, above, below and within.
Whatever your individual theory, the number seven is believed to be a magical or lucky number, and can be used to indicate appreciation and knowledge of fairies.