modeling cohesive element

hello,

 i am modelling a concrete beam with FRP bonded to beam with the adhesive. i hav tried to simulate adhesive using cohesive element Abaqus(from manual) for the past 2 months, but am getting missing  property definition for those elements.I am not sure the procedure I hav followed is correct, so please send me the procedure for modelling cohesive element and the contact between the adherent faces.

waiting for the  reply