Sit down and discuss the deal with your band mates. At this point it is not important whether or not you understand all of the particulars of the deal; what is important is that you read it thoroughly and pull from it what you can and discuss the parts of the deal that you understand. It is necessary to open up conversation within the band as soon as possible before the process really gets under way.
Hire the services of an entertainment lawyer and have the lawyer look the contract over. An entertainment lawyer will understand the nuances of a record deal that a corporate contract lawyer may miss.
Discuss the deal with the lawyer; at this point you will want to dive into the details and discuss what you do and do not want from it. Since you already opened up conversation about the deal with the band earlier, having the conversation about it now that you understand it becomes easier.
Submit any changes you need in the deal back to the record company and allow your entertainment lawyer to negotiate on your behalf. The artist should not get involved in the negotiations, as the legal details can become frustrating. Your lawyer will keep you updated on the progress, and any changes can be discussed at that point.
Sign the deal once you have something that your lawyer and the record label agree to. Always sign the deal in the presence of your attorney and the label's attorney to make sure it is accepted as valid.