Simplified Heuristics to convert ER diagram to tables:

N : M   E1 related to E2 through N : M relationship R
  3 tables:
    * E1 contains attributes of E1
    * E2 contains attributes of E2
    * R contains:
       attributes of R
       foreign key (FK) referencing primary key (PK) in E1
       FK referencing PK in E2 
    
1 : N  E1 related to E2 through 1 : N relationship R
(one E1 entity related to multiple E2 entities)
    2 tables:
      * E1 contains attributes of E1
      * E2 contains:
         attributes of E2
         FK referencing PK in E1
         attributes of R
        
1 : 1  E1 related to E2 through 1 : 1 relationship R
    1 table contains:
        * attributes of E1
        * attributers of E2
        * attributes of R