For a quick and dirty project, what are some of the simplest ways to reduce the power use of an Arduino?
Imagine the following setup:
A typical Arduino Nano, hooked up to a pair of DS18B20s and one of the mini OLED screens. Power comes from a cellphone battery hooked to a TP4056 board, which then runs to a small 0.9V >> 5V boost board, both common eBay items.
The idea is to make a basic platform, to which additional functionality will be slowly added, such as a wireless link and data-logging. For now, though, the situation is as described above.
The obvious start would no doubt be killing off unnecessary LEDS , or at least, tacking on extra resistance to make them fainter. Maybe finding how to reduce the brightness of the OLED screen would also be an obvious step, and that green LED next to the ON switch isn't necessary...
But beyond this, what simple steps could be done in coding or hardware load-out could help get more battery time?
(This question relates to a specific level of embedded system enthusiast, namely, the intermediate level, someone who isn't yet confident enough to dive into the depths of the AVR assembly language, but rather someone who already grasps the basics of how electronics and embedded devices are put together in a system (In other words, myself..). There are differences compared to the How can I get my atmega328 to run for a year on batteries? question, and more specific to the actions I practically can take.)