Osborne's well-made play in three acts, Look Back in Anger, does make a significant use of symbols to convey its thematic implications. Let me approach your question with some examples:
1) Church Bells ringing on Sunday evenings symbolises the religious establishment that the angry young protagonist believes to be an encroachment into his domestic space. We hear Jimmy resort to loud jazz trumpet as a mode of protest. The symbolic binaries relate to the basic theme of the Individual-Establishment confrontation.
2)Alison Porter's ironing board symbolises a narrowly circumscribed domestic space that she finds for herself, an obsessive preoccupation to maintain a cold, non-responsive stance for which Alison is put to onslaught and abuses by Jimmy. The break-down of the ironing board symbolises the break-down of the illusion of peace and aloofness.
3) The bear and squirrel game in which Jimmy and Alison assume the roles of an old bear and a cute little squirrel respectively with Cliff Lewis playing the added role of a mouse is a symbolic episode suggesting a primitive natural world of fairy-tale happiness into which Jimmy and Alison want to take a protective shelter.
4) Scattered newspapers in the Porter apartment may be symbolic of the real world as scattered, broken and full of futile repetitions.
5) The red shirt of Jimmy Porter as worn by Alison at the beginning of act I and by Helena in the beginning of act III may symbolically relate to the themes of love and sexuality.