The first step is to figure out how much future money you have coming to you. That means looking at the documents that set up your structured settlement, and finding out how many additional payments you have coming to you and how much each payment is for. This can be a trivial task, as in 36 more payments of $400, or a very complex task with phased payments, lump sums, and varying amounts for a lengthy period of time.
Once you have this figured out, perform a net present value calculation using a high and a low discount rate so that you know what the present value of your future payments is. This is the starting point for all your negotiations.