1. You can not win a negotiation that you can not afford to lose. What are you negotiating if anything is acceptable?
2. Negotiation is neither an art nor a science. No two negotiations are the same. You must learn the rules and the art (Yes, you can learn it!), because formulas won't help much.

Here's some food for thought: There is no need to negotiate if you are not interested in the position. However, if you are truly interested in the position, it is in the interest of both parties to explore the areas of flexibility, the areas where negotiations can produce an acceptable outcome for the overall compensation package. Being reasonable and empathetic with the other party will lead to satisfactory outcomes. Negotiate on all potential dimensions of the compensation package. Know your constraints and what is acceptable, and learn their constraints. If differences remain large, be prepared to walk away. As the song goes - know when to hold'm, know when to fold'm, know when to walk away, and know when to run. Prolonged negotiations, without progress, are just a waste of time.

Be Prepared to Answer -

What is an acceptable offer for you? or, What will it take for you to accept employment with us? If we make you this offer, will you accept it right now? What other differently structured offers would be acceptable? What do you think is the fair-market compensation for someone like you in this industry and in this geographic area? How low can you go on each dimension of the compensation package, keeping in mind that lowest compensation on each dimension is unacceptable? Which dimension do you wish to maximize? Are we in the "ball park" (i.e. within reasonable difference) that we can get to a reasonable offer for you? What other offers do you have? What compensation do they offer? If you have such better paying offers, why are you talking to us? By when do you expect to make your decision? Would it help you make up your mind, if we arrange for you to talk to some senior executives?

Be Prepared to Ask -

How about considering (code word for negotiating) other dimensions of the package, beyond annual salary and job title? For example, signing bonus, annual bonus, vacation, retirement plan, equity options, etc. What other differently structured compensation packages can you offer me? Do you have flexibility on: salary, signing bonus, annual bonus, or anything else? When you say that you would need approval from higher ups, who would that be and is it possible to get such approval now?