The reconstruction of a warm inflationary universe model from the scalar spectral index n_S(N) and the tensor to scalar ratio r(N) as a function of the number of e-folds N is studied. Under a general formalism we find the effective potential and the dissipative coefficient in terms of the cosmological parameters n_S and r considering the weak and strong dissipative stages under the slow roll approximation. As a specific example, we study the attractors for the index n_S given by n_{S}-1propto N^{-1} and for the ratio rpropto N^{-2}, in order to reconstruct the model of warm inflation. Here, expressions for the effective potential V(phi ) and the dissipation coefficient Gamma (phi ) are obtained.