If you are applying to the University of Oxford’s BA (Hons) in English Language and Literature, here are some posts with advice and tips:
How to Prepare for an Application to Oxford for English
An Oxford English Interview Poem
Seven Tips for Dealing with Unseen Poems in Oxford Interviews
Keble College provides useful general feedback on each admissions round on their English subject page (see the right-hand column).
University College’s Staircase 12 website brings together lots of relevant information.
The University of Oxford has some great advice and videos of sample interviews.
Information about preparing for the ELAT test can be found here. You should look at the past papers and marking criteria, as well as paying close attention to the online presentation An introduction to the English Literature Admissions Test (ELAT).