When you say split, I presume you're referring to subdividing? First, you will need to contact the town zoning office in which the property is located (have your tax map # handy). They will be able to tell you what the minimum requirements are for subdividing/and if it is even possible. If it is indeed possible, you will want a survey done showing your proposed new lot lines. After that, you will need to attend the towns planning board or zoning board meeting in order for your subdivision to be approved. These meetings are often times only once a month, and you will need to get your name on the agenda.
I am located in the Southern Adirondacks (Chestertown/Brant Lake area). If I can be of any further help, please let me know.