How is it best to learn the set texts?

Don't just memorise the English translation! Make sure you understand how the sentence fits together grammatically e.g. identify the subject, object and the main verb and see what agrees. Then make a note of all the vocab you are unsure about and learn it separately. If there are any difficult sentences/passages just learn them as a phrase. Once you have the translation nailed, it is so much easier to comment on the style of the passage when you know the meaning! Start with the obvious by looking at the structure of the line (e.g. emphatic positioning, use of the historic present etc.) and then look for any context you can explain too.