Taking a bistable system as a research object, the strategy of choosing parameters for affecting and producing stochastic resonance (SR) is investigated. The system parameters of the bistable system and the frequency parameter of twice sampling are related to each other intrinsically. Their variation can cause changes in the height of the potential barrier, the distance of the potential wells and the transition speed of the particle, causing redistribution of the relative noise energy and leading to different stochastic resonance effects. According to the regularity of the parameter choice for the stochastic resonance, the optimal stochastic resonance can be obtained by choosing these parameters properly, which lays the foundation for further data processing.