Fight the temptation to look at the script and read it. Look it over and remember as much of you can of the lines. Keep a finger on the part you are acting out for a quick reference at a glance. Becoming the character creates more of an impression than knowing a script word for word especially when you have not seen it before. Instead, pay attention to the director's feedback. In addition watch the person you are auditioning with. Turn the reading into communication with the other actor or actors with you in the audition. Aside from the director pretend the others doing the scene with you are the only ones in the room and play off their performance and body language.
Prepare yourself for cold readings. Since they contribute to a large degree in the success of your career give yourself an advantage by being prepared. Though you cannot see the script early, you can learn and practice in other ways. For example,the AP Actors Pages website advises taking a cold reading class or workshop. Part of the cold reading technique is adapting yourself to change and the unexpected. A class or workshop teaches you how to adapt not react in a panic during cold readings.
Practice at home as well by using a newspaper or something you have not read previously. Read a headline or paragraph from the paper. Put it down and speak on it from memory. Repeat this throughout the article. This helps with instant memorization technique and assists you with delivering spoken words without having studied them at length.
Research the production if possible. When auditioning for a movie or play that has been done before try to see the original version. If there is a prior book or novel you should read it. This gives you a working knowledge of the characters and a glimpse into how to apply basic character concepts to your cold reading.
Stop reading word by word. Most people learn to read at a young age by reading the words in a sentence. Instead, as Mark Westbrook coaches on "The Acting Blog," teaching yourself the skill of reading sentences at a glance is desirable. Try to gather information of who is doing what at a glance, Understanding this and how to read sentences instead of words improve your chances of memorizing a script in the short time allowed before the audition,