Energy and lifetime are the most important design objectives in many wireless sensor network applications. In asymmetrical sensor networks, different sensors with various abilities are used. It is crucial to select the parameters of fit function and monitoring sensors optimally in a point coverage network. In this paper, our approach uses genetic algorithm to optimize the parameters of monitoring sensor selection for each round in a point coverage network. Optimal selection of covering nodes for point coverage is done by effective deletion of redundant nodes, considering data transmission cost and heeding the energy of relay nodes for the whole previous lifetime of the network. Reducing the number of active sensors, in a covering set, saves more energy and consequently increases lifetime. Simulation results demonstrate that our algorithm to optimize selection parameters is effective in lifetime prolonging and energy consumption reduction for each round or the whole time of network activity.