If you do decide to use a contract (and there are good arguments for and against... personally, I think the best reason to have one is simply for the fantasy of 'having a contract' - basically putting into words that committment to each other) then that contract should be a personal and intimate document. Some see them as marriage vows, for example. After all, what is the traditional marriage oath to 'love, honour and obey' than a form of BDSM contract? So, I think it should be poetic, beautiful and indictative of the love, respect and committment between two (or more) people.

It should certainly contain all the hard and soft limits the sub has mentioned. It should also outline the duties and responsibilities of both parties. By this I mean that it is not only the slave who is bound by the contract - the Dom/me has responsibilities too. It may include a detailed list of duties alongside a list of punishments for breaking those (Slave must cook Master's breakfast every day at 8am unless given leave, failure to do this will mean kneeling blindfolded in the corner for 30 minutes) or it may be more vague than that (slave must cater for all Master's needs, failure will result in punishment). But basically, whatever the two of you decide to put into this document is what goes in there. There is no set format. It is an agreement between two people with no backing in law and only a minimal support from the lifestyle (no one is going to ostrachise you for breaking a contract... unless it is a really bad situation...)

Basically, I see it as a fun thing you do both to help define your relationship more formally and to live out that fantasy of 'being a contracted slave'.