What causes amino acids to fold in different patterns to form different looking structures?

Hydrogen bonding

Explanation:

Hydrogen bonding causes folding in different patterns of amino acids. This folding is responsible for the formation of different structures of proteins. This folding also helps in producing the secondary structure of protein. This hydrogen bond is present between amino groups and carboxyl groups which helps them in folding their structure in different patterns.

a = executive branch; b = judicial branch