You are probably best creating DB roles and applying the permissions to that role,
CREATE ROLE UPDATE_ROLE
GRANT EXECUTE ON [dbo].SP TO [UPDATE_ROLE]
GRANT SELECT, DELETE, INSERT, UPDATE ON [dbo].[tblStartup] TO [UPDATE_ROLE]
Makes sense to do this so you can add users to this role and only need to define the permissions once for the role and then add users to the role.