Hi...plaster is not such an easy job but can be done by the DIYer. The plaster needs something to bond to, so you would have to attach something called lathe to the framing. Another alternative is a drywall-type product called blueboard. You install it like drywall but the cornerbeads are slightly different. Mesh tape is used at the joints and covered with plaster. If I recall it takes two coats, one for a base and the other for a smoother finish coat (you don't sand it like drywall compound so a smooth finish should be attained. Plaster can be bought in bags (powder form) and mixed to working consistency.