Strategy-wise, the fundamental HFT strategy is to detect large orders from banks or hedge funds as they are filled on one exchange, conjecturing that the order may have been split between multiple exchanges, and the using their speed advantage to front-run the order on other exchanges by a few milliseconds. This is what is describe in Michael Lewis' book Flashboys.
Most of these strategies are simple in concept but extremely difficult in execution. Many of them also rely on fine-grained understanding of the exchange's internal mechanisms, things that most traders would not know or be able to figure out.
I enjoyed my time in HFT, it is a fun game to play for a while, but stressful and ultimately unsatisfying as a career trajectory unless you are making serious cash.
Most of these strategies are simple in concept but extremely difficult in execution. Many of them also rely on fine-grained understanding of the exchange's internal mechanisms, things that most traders would not know or be able to figure out.
I enjoyed my time in HFT, it is a fun game to play for a while, but stressful and ultimately unsatisfying as a career trajectory unless you are making serious cash.