Well, I have come to understand persons with the following traits will be usually be Sorted to Slytherin
- Resourcefulness
- Cunning
- Ambition
- Leadership Qualities
- Self-Preservation
- Determination
- Cleverness
- Fraternity
- Power
On which trait(s) was Snape Sorted into Slytherin?
One more point: Lily Evans was Sorted before Snape, and when she was placed in Gryffindor, obviously Snape wanted to be in Gryffindor too, because Lily is his only friend.
So why is he Sorted into Slytherin? Is there a stronger reason for the Sorting Hat to override his preference and Sort him into Slytherin?