OP is unlike modern accents in that – in the absence of time travel – there is no place one can go to to hear people use it natively; on the other hand, there is now a good range of illustrations online, and these should be listened to first. Unless you have an incredibly good ear, it’s useful also to have a basic ability in phonetics, at least to the extent of being able to read and sound out the features of OP reflected in the transcriptions.