A wide range of steganography techniques has been described in this paper. Beside the evaluation of embedding parameters for the existing techniques, two problems -weaknesses-of substitution techniques are investigated which if they could be solved, the large capacity -strength-of substitution techniques would be practical. Furthermore, a novel, principled approach to resolve the problems is presented. Using the proposed genetic algorithm, message bits are embedded into multiple, vague and higher LSB layers, resulting in increased robustness.