I've always thought of this in terms of "improving the first derivative", or working not only on current knowledge but on the rate at which we are acquiring knowledge. Improved tools are a great way to increase the rate of change. Some other techniques are improving understanding of foundational topics (dependencies), inventing better representations of the problem domain (e.g., notation in mathematics and computer science), improving one's health (so as to operate at peak efficiency) through things like good diet and exercise (there are many cognitive benefits of exercise), and to the extent that fluid intelligence may be malleable, working to improve intelligence itself (e.g., dual n-back as in the 2008 Jaeggi et al. study).